Remove accidental print statement
Don't write files to the current working directory

parsetab.py now lives in source control rather than in the repo, and parser.out
isn't generated anymore since it was just for debugging anyway.

In order to actually update the parser, you now need to set the environment
variable SHOULD_REBUILD_PARSER to 1 and parsetab.py will be automatically
overwritten. By default, though, it's just imported directly and never written.