mofe GIVEREF() before PyTuple_SET_ITEM() call because that's when we still own the reference (pypy needs it that way)

patch Generator ABC into "collections.abc" when using Cython generators so that foreign code can test for the Generator protocol instead of the generator type

make sure all identifiers are EncodedString objects

This is more consistent with the execution of "python foo.py" and
also allows for compilation of files that don't obey the module
naming rules.

avoid dependency of module patching code on order of utility code sections in C file (had to come after "Generator" code by accident in order to work)

Conflicts:
	CHANGES.rst

fix stupid C-API misuse: accidentally passed a NULL pointer to PyObject_GetItem() instead of a 0 integer index to PySequence_GetItem()

When merging a transitive_list, copy the list