The code was sucking. To the extent that maintenance was hard. It's a lot
easier to work with code that is sensibly split at sensible boundaries. So
now it is more like that.

But the refactor is minimal. Because we don't want you to have more merge
hell than absolutely necessary.

If you merge you will need to pay attention to brew.h.rb (as it is deleted)
and bin/brew (as command logic is gone). It will be painful, but you will just
have to help git out by moving any changes around manually.

Note compatibility.rb. It ensures that any function renames or removals don't
break anything. We're pretty serious about backwards compatibility. And that's
because we encourage you to hack around with the innards. And we couldn't do
that if we would then just make stuff disappear behind your back.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>

The update_git_pull_output_with_formulae_changes fixture (which consists
of mocked-up `git pull` output) listed a few files as both updated and
deleted.  This caused the test_update_homebrew_with_formulae_changes test to
fail.  My guess is that this fixture was mocked-up before formula deletion
handling was introduced, and became broken when it was.  This revision just
makes this fixture internally consistent, and allows the associated test to
pass.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>

Sphinx currently has a download name 'http://sphinxsearch.com/downloads/sphinx-1.10-beta.tar.gz', which homebrew currently can't correctly identify - with a small change to the regex for 'foobar-4.5.0-beta1' (make that trailing number optional) - it works like a charm.

Signed-off-by: David Höppner <0xffea@gmail.com>