Finalize core

All operations are now created with builders for consistency.

Operations which require more than a simple response type have
the response class as a public static nested class.

At the core we no longer cache and return query information. This
will be handled in the user API level.

Also - this is updated to use the current `develop` of `riak_pb`. Specifically, the field for the YZ index in bucket props had its name and thus getter method names changed.