chore(module): move files around in preparation for more modules

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+'use strict';
+
+/**
+ * @ngdoc service
+ * @name angular.module.ng.$q
+ * @requires $rootScope
+ *
+ * @description
+ * A promise/deferred implementation inspired by [Kris Kowal's Q](https://github.com/kriskowal/q).
+ *
+ * [The CommonJS Promise proposal](http://wiki.commonjs.org/wiki/Promises) describes a promise as an
+ * interface for interacting with an object that represents the result of an action that is
+ * performed asynchronously, and may or may not be finished at any given point in time.
+ *
+ * From the perspective of dealing with error handling, deferred and promise apis are to
+ * asynchronous programing what `try`, `catch` and `throw` keywords are to synchronous programing.
+ *
+ * <pre>
+ *   // for the purpose of this example let's assume that variables `$q` and `scope` are
+ *   // available in the current lexical scope (they could have been injected or passed in).
+ *
+ *   function asyncGreet(name) {
+ *     var deferred = $q.defer();
+ *
+ *     setTimeout(function() {
+ *       // since this fn executes async in a future turn of the event loop, we need to wrap
+ *       // our code into an $apply call so that the model changes are properly observed.
+ *       scope.$apply(function() {
+ *         if (okToGreet(name)) {
+ *           deferred.resolve('Hello, ' + name + '!');
+ *         } else {
+ *           deferred.reject('Greeting ' + name + ' is not allowed.');
+ *         }
+ *       });
+ *     }, 1000);
+ *
+ *     return deferred.promise;
+ *   }
+ *
+ *   var promise = asyncGreet('Robin Hood');
+ *   promise.then(function(greeting) {
+ *     alert('Success: ' + greeting);
+ *   }, function(reason) {
+ *     alert('Failed: ' + reason);
+ *   );
+ * </pre>
+ *
+ * At first it might not be obvious why this extra complexity is worth the trouble. The payoff
+ * comes in the way of
+ * [guarantees that promise and deferred apis make](https://github.com/kriskowal/uncommonjs/blob/master/promises/specification.md).
+ *
+ * Additionally the promise api allows for composition that is very hard to do with the
+ * traditional callback ([CPS](http://en.wikipedia.org/wiki/Continuation-passing_style)) approach.
+ * For more on this please see the [Q documentation](https://github.com/kriskowal/q) especially the
+ * section on serial or parallel joining of promises.
+ *
+ *
+ * # The Deferred API
+ *
+ * A new instance of deferred is constructed by calling `$q.defer()`.
+ *
+ * The purpose of the deferred object is to expose the associated Promise instance as well as apis
+ * that can be used for signaling the successful or unsuccessful completion of the task.
+ *
+ * **Methods**
+ *
+ * - `resolve(value)` – resolves the derived promise with the `value`. If the value is a rejection
+ *   constructed via `$q.reject`, the promise will be rejected instead.
+ * - `reject(reason)` – rejects the derived promise with the `reason`. This is equivalent to
+ *   resolving it with a rejection constructed via `$q.reject`.
+ *
+ * **Properties**
+ *
+ * - promise – `{Promise}` – promise object associated with this deferred.
+ *
+ *
+ * # The Promise API
+ *
+ * A new promise instance is created when a deferred instance is created and can be retrieved by
+ * calling `deferred.promise`.
+ *
+ * The purpose of the promise object is to allow for interested parties to get access to the result
+ * of the deferred task when it completes.
+ *
+ * **Methods**
+ *
+ * - `then(successCallback, errorCallback)` – regardless of when the promise was or will be resolved
+ *   or rejected calls one of the success or error callbacks asynchronously as soon as the result
+ *   is available. The callbacks are called with a single argument the result or rejection reason.
+ *
+ *   This method *returns a new promise* which is resolved or rejected via the return value of the
+ *   `successCallback` or `errorCallback`.
+ *
+ *
+ * # Chaining promises
+ *
+ * Because calling `then` api of a promise returns a new derived promise, it is easily possible
+ * to create a chain of promises:
+ *
+ * <pre>
+ *   promiseB = promiseA.then(function(result) {
+ *     return result + 1;
+ *   });
+ *
+ *   // promiseB will be resolved immediately after promiseA is resolved and it's value will be
+ *   // the result of promiseA incremented by 1
+ * </pre>
+ *
+ * It is possible to create chains of any length and since a promise can be resolved with another
+ * promise (which will defer its resolution further), it is possible to pause/defer resolution of
+ * the promises at any point in the chain. This makes it possible to implement powerful apis like
+ * $http's response interceptors.
+ *
+ *
+ * # Differences between Kris Kowal's Q and $q
+ *
+ *  There are three main differences:
+ *
+ * - $q is integrated with the {@link angular.module.ng.$rootScope.Scope} Scope model observation
+ *   mechanism in angular, which means faster propagation of resolution or rejection into your
+ *   models and avoiding unnecessary browser repaints, which would result in flickering UI.
+ * - $q promises are recognized by the templating engine in angular, which means that in templates
+ *   you can treat promises attached to a scope as if they were the resulting values.
+ * - Q has many more features that $q, but that comes at a cost of bytes. $q is tiny, but contains
+ *   all the important functionality needed for common async tasks.
+ */
+function $QProvider() {
+
+  this.$get = ['$rootScope', '$exceptionHandler', function($rootScope, $exceptionHandler) {
+    return qFactory(function(callback) {
+      $rootScope.$evalAsync(callback);
+    }, $exceptionHandler);
+  }];
+}
+
+
+/**
+ * Constructs a promise manager.
+ *
+ * @param {function(function)} nextTick Function for executing functions in the next turn.
+ * @param {function(...*)} exceptionHandler Function into which unexpected exceptions are passed for
+ *     debugging purposes.
+ * @returns {object} Promise manager.
+ */
+function qFactory(nextTick, exceptionHandler) {
+
+  /**
+   * @ngdoc
+   * @name angular.module.ng.$q#defer
+   * @methodOf angular.module.ng.$q
+   * @description
+   * Creates a `Deferred` object which represents a task which will finish in the future.
+   *
+   * @returns {Deferred} Returns a new instance of deferred.
+   */
+  var defer = function() {
+    var pending = [],
+        value, deferred;
+
+    deferred = {
+
+      resolve: function(val) {
+        if (pending) {
+          var callbacks = pending;
+          pending = undefined;
+          value = ref(val);
+
+          if (callbacks.length) {
+            nextTick(function() {
+              var callback;
+              for (var i = 0, ii = callbacks.length; i < ii; i++) {
+                callback = callbacks[i];
+                value.then(callback[0], callback[1]);
+              }
+            });
+          }
+        }
+      },
+
+
+      reject: function(reason) {
+        deferred.resolve(reject(reason));
+      },
+
+
+      promise: {
+        then: function(callback, errback) {
+          var result = defer();
+
+          var wrappedCallback = function(value) {
+            try {
+              result.resolve((callback || defaultCallback)(value));
+            } catch(e) {
+              exceptionHandler(e);
+              result.reject(e);
+            }
+          };
+
+          var wrappedErrback = function(reason) {
+            try {
+              result.resolve((errback || defaultErrback)(reason));
+            } catch(e) {
+              exceptionHandler(e);
+              result.reject(e);
+            }
+          };
+
+          if (pending) {
+            pending.push([wrappedCallback, wrappedErrback]);
+          } else {
+            value.then(wrappedCallback, wrappedErrback);
+          }
+
+          return result.promise;
+        }
+      }
+    };
+
+    return deferred;
+  };
+
+
+  var ref = function(value) {
+    if (value && value.then) return value;
+    return {
+      then: function(callback) {
+        var result = defer();
+        nextTick(function() {
+          result.resolve(callback(value));
+        });
+        return result.promise;
+      }
+    };
+  };
+
+
+  /**
+   * @ngdoc
+   * @name angular.module.ng.$q#reject
+   * @methodOf angular.module.ng.$q
+   * @description
+   * Creates a promise that is resolved as rejected with the specified `reason`. This api should be
+   * used to forward rejection in a chain of promises. If you are dealing with the last promise in
+   * a promise chain, you don't need to worry about it.
+   *
+   * When comparing deferreds/promises to the familiar behavior of try/catch/throw, think of
+   * `reject` as the `throw` keyword in JavaScript. This also means that if you "catch" an error via
+   * a promise error callback and you want to forward the error to the promise derived from the
+   * current promise, you have to "rethrow" the error by returning a rejection constructed via
+   * `reject`.
+   *
+   * <pre>
+   *   promiseB = promiseA.then(function(result) {
+   *     // success: do something and resolve promiseB
+   *     //          with the old or a new result
+   *     return result;
+   *   }, function(reason) {
+   *     // error: handle the error if possible and
+   *     //        resolve promiseB with newPromiseOrValue,
+   *     //        otherwise forward the rejection to promiseB
+   *     if (canHandle(reason)) {
+   *      // handle the error and recover
+   *      return newPromiseOrValue;
+   *     }
+   *     return $q.reject(reason);
+   *   });
+   * </pre>
+   *
+   * @param {*} reason Constant, message, exception or an object representing the rejection reason.
+   * @returns {Promise} Returns a promise that was already resolved as rejected with the `reason`.
+   */
+  var reject = function(reason) {
+    return {
+      then: function(callback, errback) {
+        var result = defer();
+        nextTick(function() {
+          result.resolve(errback(reason));
+        });
+        return result.promise;
+      }
+    };
+  };
+
+
+  /**
+   * @ngdoc
+   * @name angular.module.ng.$q#when
+   * @methodOf angular.module.ng.$q
+   * @description
+   * Wraps an object that might be a value or a (3rd party) then-able promise into a $q promise.
+   * This is useful when you are dealing with on object that might or might not be a promise, or if
+   * the promise comes from a source that can't be trusted.
+   *
+   * @param {*} value Value or a promise
+   * @returns {Promise} Returns a single promise that will be resolved with an array of values,
+   *   each value coresponding to the promise at the same index in the `promises` array. If any of
+   *   the promises is resolved with a rejection, this resulting promise will be resolved with the
+   *   same rejection.
+   */
+  var when = function(value, callback, errback) {
+    var result = defer(),
+        done;
+
+    var wrappedCallback = function(value) {
+      try {
+        return (callback || defaultCallback)(value);
+      } catch (e) {
+        exceptionHandler(e);
+        return reject(e);
+      }
+    };
+
+    var wrappedErrback = function(reason) {
+      try {
+        return (errback || defaultErrback)(reason);
+      } catch (e) {
+        exceptionHandler(e);
+        return reject(e);
+      }
+    };
+
+    nextTick(function() {
+      ref(value).then(function(value) {
+        if (done) return;
+        done = true;
+        result.resolve(ref(value).then(wrappedCallback, wrappedErrback));
+      }, function(reason) {
+        if (done) return;
+        done = true;
+        result.resolve(wrappedErrback(reason));
+      });
+    });
+
+    return result.promise;
+  };
+
+
+  function defaultCallback(value) {
+    return value;
+  }
+
+
+  function defaultErrback(reason) {
+    return reject(reason);
+  }
+
+
+  /**
+   * @ngdoc
+   * @name angular.module.ng.$q#all
+   * @methodOf angular.module.ng.$q
+   * @description
+   * Combines multiple promises into a single promise that is resolved when all of the input
+   * promises are resolved.
+   *
+   * @param {Array.<Promise>} promises An array of promises.
+   * @returns {Promise} Returns a single promise that will be resolved with an array of values,
+   *   each value coresponding to the promise at the same index in the `promises` array. If any of
+   *   the promises is resolved with a rejection, this resulting promise will be resolved with the
+   *   same rejection.
+   */
+  function all(promises) {
+    var deferred = defer(),
+        counter = promises.length,
+        results = [];
+
+    if (counter) {
+      forEach(promises, function(promise, index) {
+        ref(promise).then(function(value) {
+          if (index in results) return;
+          results[index] = value;
+          if (!(--counter)) deferred.resolve(results);
+        }, function(reason) {
+          if (index in results) return;
+          deferred.reject(reason);
+        });
+      });
+    } else {
+      deferred.resolve(results);
+    }
+
+    return deferred.promise;
+  }
+
+  return {
+    defer: defer,
+    reject: reject,
+    when: when,
+    all: all
+  };
+}