Mock out ZK client in HBaseComponent as called by TopologyScheduler.
Start moving HBaseComponent.setHTableMetadata to TopologyScheduler.
TopologyScheduler no longer reads metadata from zookeeper.

It still publishes it there.
HBaseComponent fetches region metadata from zookeeper.
HBaseComponent no longer writes to zookeeper.

Instead it only reads from it, in getRegionMetadata (called after start()).

Further, drop the use of getComponentConfiguration().  A subtle quirk in how storm builds its thrift requests prevents properties set directly by the topology submitter from showing up in the map.  However they are still present in the underlying thrift object; we just need to json parse it out ourselves.

This completes the change of direction for flow of region metadata: now it is discovered and published by the scheduler, and consumed by the components.