v3.0.0

Changed

Breaking: Look for documents using an ObjectId.

IDs in MongoDB can be stored as either strings or Object IDs. This meant that if you created a document
and let Mongo assign an id to it, Esix wouldn't be able to find it as it was only looking for the
hex representation.

With this change, BaseModel.find(id) will look for documents with either a matching Object id or
a string representation of it.