Update harness to project 4
Remove executable bit from files
Add ast.{c,h}pp to gitignore, astbuilder.gawk executable
Merge branch 'master' into harness2

Remove token tests.

Conflicts:
	.gitignore
	ast2dot.cpp
	attribute.hpp
	lexer.l
	main.cpp
	parser.ypp
	primitive.hpp
	symtab.cpp
	symtab.hpp
Fix indentation
Add tags target for Makefile
Add tests from everywhere, add AST checking
Capture segmenation fault
Implement visitIdent
Implement many expresssions
Add while loop support
Correct tests, implement assignment
Implement constant folding for expressions, assignment
Implement call, fix and/or, implement param, decl
Make all variables TOP after a function call
Make tests more easy to manually replicate
Higher scope vars are TOP, not BOTTOM. BOTTOM propagates