A couple of changes to host the PyAPNs egg ourselves

There hasn't been a release since 2012, but the github repo remains active. We need some of the recent changes to support interactive notifications in iOS 8. Until there is an official release we can host the egg.

Jira: http://jira.wapolabs.com/browse/RP-251

Reviewers: @tburke @anazarov @brianneumann @derelk @gracedo