Refactor odl-mdsal-distributed-datastore
odl-mdsal-distributed-datastore forms the baseline for supporting
akka-based cluster. This refactors it to pull its dependencies in
so it can be properly tested.
This also moves CommitStatsMXBean, so we do not depend on controller's
broker at all.
Finally we co-locate all configuration files into this feature, so
it can boot up.
JIRA: CONTROLLER-1584
Change-Id: I9319de78d61d63e3c49825e940af5c8c70657185
Signed-off-by: Robert Varga <robert.varga@pantheon.tech>