Fixed potential bug in the way we create an AkkaSystem when none is specified to prevent creating multiple ones with the same name
Upgraded to the latest Spray nightly build
Implemented correct behaviour for resolving conflicts and writing the result back to riak
Added unit test for conflict resolution and fixed the bugs that inevitably revealed.

No support for setting bucket properties yet so for now I've set the relevant test bucket properties manually. Added TODO and signatures for bucket property support