Add CRDT support Fixes #310
Added tests for serialization of CDRT ops
Add itests for crdt ops
Add RiakDatatype to return server generated key
Address issues from Sean's comments

- Flag default to false
- Remove phantom add from CrdtSet
- Ship all set modifications, don't try to infer user intention
Remove CrdtSet phantom add
Add bucket type as required field on CRDT update op
Make tests actually compile with bucket type change
A proof of concept CRDT API with simple integration test
Add itests
Java types, how do they even work
add set to example, in addition to some documentation
touch-up
Play with a read/write interface for Riak datatypes