Resolved issues with using peewee on app engine.
I think I might take a crack at this myself. I'm surprised that there's no sqlite on GAE!
 Fixed in 6838d8ec54093ebefca4b436abff601e14f94795 -- thanks for the diff and bringing this to my attention! Look forward to more PRs in the future!

App Engine does not support sqlite3 so in order to get peewee to work I had to add in checks for it. This was my quick and dirty solution. There's probably a more elegant way to handle this.
