[python-committers] Promote Xiang Zhang as a core developer

Hi,

Last months, I noticed that Xiang Zhang is very active on the bug tracker and propose many enhancements and bug fixes. He contributes to Python code, but also to the C code (a rare skill nowadays). Slowly, he understood how to produce "good" patches, the CPython workflow, etc. I think that his contributions are now good enough to give him the commit bit.

As I did previously (for Xavier), I also propose to be his mentor the first month: request him to ask me before pushing anything, help him with Mercurial, branches, etc. So I can help to avoid simple mistakes and to not break the buildbot too often :-)

Maybe Serhiy Storchaka and/or Yury Selivanov may want to co-mentor Xiang? Serhiy reviewed many of Xiang's patches recently.

Victor