C functions with no arguments should use (void).
Initial work on using clang to generate code.
gen.py: use all defines fron pnacl-clang.

Passing -undef to Index.parse undefines all predefined macros. We can
then pass the defines extracted from running pnacl-clang so the build
will be consistent with a pnacl build.
WIP on generation glue.c code.

I'm starting to think that instead of having a library that must be
linked to the glue code, that everything should be generated in one
file. For now, the glue code I'm generating is the same as before,
without the necessary includes.
WIP on glue.js
Add type.js and tests.

Disable module and typebuilder tests. They'll probably be
changed/removed.
Add tests for casting numerics
Add jshint stuff, and fix warnings
Add "unused" jshint option.
Run jshint as a pretest script
Rename 2nacl -> naclbind
Add void type cast tests