progress on float and int casting
tentatively through semantic checking and SAST
add number casting
generating of int and float casting works
fixed merge conflicts
better parser errors

closes #64
generalize casting and resolve SR conflicts
Merge branch 'better_parsing_errors' into more-casting
semantically checked proper casting
code gen for casting
organizing
Merge pull request #103 from rapid-lang/better_parsing_errors

better parser errors
remove unused tokens
Merge pull request #96 from rapid-lang/more-casting

More casting
Merge remote-tracking branch 'origin/master' into binary_ops

Conflicts:
	compiler/ast.mli
	compiler/generate.ml
	compiler/parser.mly
	compiler/sast.mli
	compiler/sast_printer.ml
	compiler/translate.ml