SolarCS/mongo_session_store — pull request #1 by mati0090 (2014-01-03 14:01:35+00:00)
Title: Overwrite existing field fixed

This one triggered
```
W, [2014-01-03T15:00:53.458471 #14206] WARN -- : Overwriting existing field _id in class ActionDispatch::Session::MongoidStore::Session.
```