Pythran 0.4 "PyHPC"

Featuring
- better OpenMP support
- several performance bug fixes
- faster numpy array indexing
- optional parameter support
- faster tuple implementation when all elements have the same type
- a few more supported module, including ``functional.partial``
- exception not caught at the C++ level are now raised at the Python
  level
- better long support
- more testing, special thanks to g webb
- several bugfixes in the C++ backend
- better None support, especially for scalar types
- add CFG analysis for better ``return None`` insertion
- better documentation!