add store name as a property of all binary stores
Create a CompositeBinaryStore that:

- initializes any number of named BinaryStore instances
- appear as a vanilla BinaryStore to existing code
- allow consumers to offer a "StrategyHint" that MAY be used to
  determine what named BinaryStore to persist content to
- on retrieval, look for the BinaryKey in all named BinaryStores
Add composite binary store support to EAP
IT
REMOVE THIS COMMIT -- lighten some Repository methods for some quick testing -- REMOVE THIS COMMIT