Rename database client classes

Update our class names to reflect the new file structure introduced in
b700c1bef89a67a64f1040fb6bb03c0320eefe91.

Use the

    module DBShell
      module Client
      end
    end

syntax intead of `DBShell::Client` so that we don't have to define the
`Client` module in a separate file and require it. Otherwise we'd get an
error:

    lib/dbshell/client/sqlite3.rb:1:in `<top (required)>': uninitialized constant DBShell::Client (NameError)

1 files changed, 15 insertions, 11 deletions

diff --git a/lib/dbshell/client/sqlite3.rb b/lib/dbshell/client/sqlite3.rb
index adc71ef..09b44f9 100644
--- a/lib/dbshell/client/sqlite3.rb
+++ b/lib/dbshell/client/sqlite3.rb
@@ -1,15 +1,19 @@
-class DBShell::Sqlite3Client
-  EXECUTABLE_NAME = 'sqlite3'
+module DBShell
+  module Client
+    class Sqlite3
+      EXECUTABLE_NAME = 'sqlite3'
 
-  def self.runshell(db_info)
-    args = self.build_command(db_info)
-    exec(*args)
-  end
+      def self.runshell(db_info)
+        args = self.build_command(db_info)
+        exec(*args)
+      end
 
-  def self.build_command(db_info)
-    args = [
-      EXECUTABLE_NAME,
-      db_info['database']
-    ]
+      def self.build_command(db_info)
+        args = [
+          EXECUTABLE_NAME,
+          db_info['database']
+        ]
+      end
+    end
   end
 end