Parallel readable store + test
Merge pull request #158 from twitter/feature/add_paralell_readable_store

Parallel readable store + test
Changes the return type of merge
bug noticed in PromiseLink
Add tests for the PromiseLink
Merge pull request #163 from twitter/merge-fix

Changes the return type of merge
Merge branch 'develop' into redis-sorted-sets-part-deux

Conflicts:
	storehaus-redis/src/main/scala/com/twitter/storehaus/redis/RedisSortedSetStore.scala