Move try_catch code into libcommon
Add root makefile

Knows how to build main pinkysim code that should build on all
supported platforms and some special tests that I will only test and
verify on OS X.

Rules supported:
  clean - Deletes output files and directories for everything.
  all - Builds the main pinkysim code.  Should work on OS X, Windows,
        and Linux.
  tests - Just builds some special test code.  Only verified to work on
          OS X.
Ignore local debug scripts