[Cython] some pull requests for 0.16?

[Stefan Behnel]

Hi,

I put up two new pull requests on github:

Implementation of PEP 380 (yield from):
https://github.com/cython/cython/pull/96

Rewrite of dict iteration:
https://github.com/cython/cython/pull/95

Given that the release of 0.16 has currently slowed down a bit, and given
that these are really nice features, could someone (and especially Mark, as
the responsible release manager) take a look at them and give an opinion
regarding their suitability for 0.16?

Personally, I think they are ready, but they'd certainly require another
beta release for testing.

You may notice that I also added the PyPy related preprocessor defines
"CYTHON_COMPILING_IN_CPYTHON" and "CYTHON_COMPILING_IN_PYPY" to the current
master and used them in a couple of places to reduce Cython's dependency on
CPython details. That doesn't mean we already support PyPy (there are still
open issues, mostly on their side). I only pushed the changes that were
non-intrusive and helped me in preparing the two branches above in a clean
way. I have some more changes in my PyPy branch:

https://github.com/scoder/cython/tree/pypy

Stefan