Version 0.2.1

This is a community powered release!

Andrew Janke (@apjanke) landed documentation fixes, made the usage of adapter consistent by removing the adaptor classes we had lying around in internal, suppressed deprecation warnings in our test cases, and made central repo links in our readme way more useful.

Gabriel Santos de Almeida (@gabrielsalmeida) created a fix for making the newly re-formatted builder pattern work for our GAE users as well.

Thanks all!