Correcting ROF coercer format
Adding Fedora::Collection

This mirrors the structure of Lotus::Models adapters.

By separating Command, Query, and Collection I'm not passing
connection information to two separate classes. Instead it is
assigned to the Collection.

Collection is responsible for persisting object's in their serialized
form, and for bringing the object back up in a similar form.

Query is responsible for filtering against the collection and
transforming from a persistence format to the memory format.

Command is responsible for transforming, via the map, an in memory
object.