Move builtin struct module to _struct to allow pypy "-m idlelib.idle"
Support compilation with gcc-4.9
Added support for the stdlib gdbm module via cffi
Annotator cleanups
Use argparse for packaging.py, and add third-party components to LICENSE file. Also mention that gdbm is GPL. Do not crash the packaging process on failure in CFFI or license-building, rather complete the build step and return -1.