source for Patchy the autobot

[Graham Percival]

In order to de-mystify Patchy, I'm going to point people at the
source:

https://github.com/gperciva/lilypond-extra/blob/master/patches/compile_lilypond_test.py

As you can see, it's pretty ugly python, but it works.  Or at
least, the testing-patches parts work.  I haven't checked
dev/staging since there's nothing there at the moment, but I'll do
that tomorrow morning.

If you look at that code and think "yikes, that's horrible.  I
could do better than that if I were drunk and typing with one
hand", then I would love it if you did that.  I'm particularly
"proud" of my inability to figure out how to use shutils and/or
os.copy and my resulting os.system("cp -r %s %s" % (src, dest)).

Note that Patchy does not need to conform to python 2.4, since
it's not something that gets run in GUB.

The general idea is:
- run compile_lilypond.staging() as a cronjob every X hours
  (completely automatic merging)
- run test-patches.py as a cronjob every X hours; this will
  prepare a regtest comparison for a human to examine before
  accepting the patch.


Again, it would be great if somebody with more patience and/or
pride in their work could take over Patchy.  As an incentive, you
don't need to deal with our review process.  I'll hand git push
ability for that repo out to anybody; just hack away and push
without any concerns for code style or readability or reviews or
whatever.

- Graham