Update to protocol buffer compiled code and related updates reenabling compilation

In response to a failure to compile on my machine, I updated the protocol buffers generated output and made the necessary changes to get things compiling and cleaned up again:

* Protocol buffers compiled to match proto distributed in source version
* RawRequest used to send requests to Riak that contain only the message code
* Import references changed in favor of package scopes
* Values passed into Riak are stored and retrieved without the JSON encode/decode process occurring within this client.