Split out tests directory into integration tests and unit tests.
Updated travis build script.
Added more to GC unit test.
Updated test.py for integration tests.
Wrote more unit tests for garbage collector, need to write some GC tests for class vars next.
Updated GC so it accounts for class variables.
Added class variable GC test.
Renamed test.
Changed langauge syntax so globals need to be prefixed with a dollar sign.  Updated langauge spec.  Replaced tabs accross files with 4 spaces.  Add (very simple) globals integration test.
Renamed input and expected results files for integration tests.
Added Makefile for unit tests.
Updated travis build script - it wasn't returning to the root gear directory.
Hopefully this fixes the silly tavis build.