The Python ecosystem works much better if we deicide our source code
is actually a module named 'newlang'.
I've been putting off changing this for a long time, but I might as
well do it now.
parse2: Move all new parser code to the parse2 namespace
...
This is a bit of a messy mass rename but it seems to work and makes things
clearer in preparation for a new parse module.
This also renames the NEWLANG_NEW_PARSE test environment variable to
NEWLANG_PARSE2.
