Update Python 2 and PyPy

* CPython 2.7.9
* PyPy 2.4.0
* meinheld==0.5.7, greenlet==0.4.5
* Fix nginx config.
I'm fine with copy or with inline edit, but here's some info: 

> prefer cp than sed because it keeps git diff clean

If you add `nginx.conf` to `.gitignore`, changes will no longer show up in `git status`, but you can still manually say `git add -f nginx.conf` if you want to update the file. This is a great way to include a "default" config in the repo while still letting everyone modify it as they need.