Merge pull request #5 from tcr/tcr-fndecl

Supports function declarations. Fix assignment ops and method calls.
Merge pull request #8 from tcr/tcr-fndecl

Many changes.
Adds TODO opassign code.
Prevents assignment hazards in a += a += a
Merge pull request #18 from tcr/tcr-assignhazard

Prevents assignment hazards. Fixes #17
Adds additional test for assignment ops.
Merge branch 'master' of https://github.com/tcr/colonyjit-compiler