Complete migration from Google Code

[techtonik]

• [x] place a redirect from https://code.google.com/p/pydotorg/ to GitHub
• [ ] change license to CC0
  • [x] add rationale that crediting is important and licensing is not
  • [x] add rationale that code must be max reused
  • [ ] ask for no patents and non-own code in guidelines
• [x] move wiki to README.md
  • [x] cut the text
  • [x] be inclusive (issue #1)
  • [x] explain relationship to python.org
• [x] process https://github.com/pydotorg/backlog/blob/master/Wiki.md