clean up directives setup in InterpretCompilerDirectives transform by moving the global part into __init__()

Clarify license position with respect to compilation output.

Thanks to Alok Singhal.

replace the currently broken BoolBinopNode by GenericBoolBinopNode to fix it and generally avoid redundancy

Add more libc and posix includes

- Add more types into posix.types
- Add new posix.resource, posix.signal and posix.time includes

Conflicts:
	CHANGES.rst
	Cython/Compiler/Nodes.py

There doesn't seem to be a good way to get at the right vtab struct here...

Conflicts:
	CHANGES.rst
	Cython/Compiler/Nodes.py