Added POST /user/gcm.
Added node 0.10.x as engine for heroku.
Redirecting to server repo on GET /.
Added 'npm start' command.
Implemented push via Google Cloud Messaging.

Untested. Probably not working.
Loading API key more transparently.
Added callback to push.sendMessage.
Fixed potential crash if callback was null.
Added brackets.
Added getPublicModel() to gcmIDs.
Getting real gcmID from database objects.
Added log message for gcm.
Merge branch 'feature/gcm'