When a Put fails due to a NotServingRegionException, the cached location
of that Region is never cleared. Thus, subsequent calls to resubmit
the Put will fail in the same way as the original, never determining
the new location of the Region.
If the Connection is not closed by the user before the Multiplexer
is discarded, it will leak resources and could cause resource
issues.
Signed-off-by: Sean Busbey <busbey@cloudera.com>