Fixed multipart response handling so it doesn't automatically try to decode the content in the event there's the possibility of partial content like a JSON snippet that isn't complete.

Now those responses will be parsed out of the multipart response and then individually run through a partial response aggregator which makes sure (at least for JSON) that only full valid JSON blocks will be sent to the decode phase.
Bumped to 0.2.4, added Riak 1.4.x 2i pagination support and migrated list keys and 2i's to only use Riak streaming results API calls behind the scenes.