Otherwise we get a runtime error when running the binary on a different
machine than the one that built it:

    $ extreload -V
    error: Failed to find the WRITE-DATE of
    /private/tmp/extreload-20220825-3720-17mi6k3/extreload_0.0.2/bundle/local-projects/:

             No such file or directory

SSL is unnecessary for our purposes, and including it causes a runtime
error when the path to `libcrypto.dylib` is different on the executing
machine than it is on the build machine.

This is the error I got when running `extreload` on an Apple Silicon
machine with Homebrew, using a package bundled by an x86 machine with
Homebrew:

    $ extreload
    debugger invoked on a SIMPLE-ERROR in thread
    #<THREAD "main thread" RUNNING {70024E0003}>:
      Error opening shared object "/usr/local/opt/openssl/lib/libcrypto.dylib":
      dlopen(/usr/local/opt/openssl/lib/libcrypto.dylib, 0x000A): tried: '/usr/local/opt/openssl/lib/libcrypto.dylib' (no such file).

    Type HELP for debugger help, or (SB-EXT:EXIT) to exit from SBCL.

    restarts (invokable by number or by possibly-abbreviated name):
      0: [CONTINUE       ] Skip this shared object and continue.
      1: [RETRY          ] Retry loading this shared object.
      2: [CHANGE-PATHNAME] Specify a different pathname to load the shared object from.
      3: [ABORT          ] Exit from the current thread.

    (SB-SYS:DLOPEN-OR-LOSE #S(SB-ALIEN::SHARED-OBJECT :PATHNAME #P"/usr/local/opt/openssl/lib/libcrypto.dylib" :NAMESTRING "/usr/local/opt/openssl/lib/libcrypto.dylib" :HANDLE NIL :DONT-SAVE NIL))
    0]

Copy the `pkg` target from Wajir to make a tarball of the bundled
dependencies in `bundle` and the Extreload source code.

This tarball can then be distributed and the program can be built and
installed from it using the Makefile. By distributing the source, an
executable can be built for more architectures and systems.

Sysexits is now in Quicklisp so we don't need to load it here.

Make it easy for package managers to build and install the program.

Add a target to create a self-contained bundle of the program that isn't
dependent on Quicklisp.

This code is based on what I did in Wajir.

With-user-abort is now in Quicklisp.