v0.2.1

Lots of changes, features and fixes here!

• Re-written the project workspace script to have separate release, debug and coverage build areas.
  • Automatic coverage reporting with travis and coveralls re-instated.
  • Top level makefile for running common tasks like documentation, building and testing.
• Added resolution of all module instantiations to their declarations.
• Fixed almost all memory leaks.
  • Remaining leaks are inside flex / bison, and need fixing still
  • Future work will allow objects to be released individually, rather than having to do it all at once.
  • Added a script for quickly getting a valgrind report.
  • Completely re-organised the ast_memory management functions and structures.
• All objects in the AST are now tagged by their source file name and their line number in the meta member.
• Relaxed the required FLEX version from 2.6 to 2.5.35