Add a zone shrinkage CLI and its tests
Print original XML for ZoneShrinkageCLI
Fix bug when RO server NPE when rolled back

An NPE might happen when a RO engine while it does not hold any
partitions. When a client queries this engine, an NPE might happen
since a pointer to an array has not been initialized. Fix is done
by doing extra null pointer checks.
RO bug fix caused by RW optimization code
Updating release_notes for release 1.6.4
Small addition to ZoneShrinkageCLITest to solve bind exception
Adding helper method in admin client to fetch remote stores xml and update specified stores in one call.
Updating build.properties and release notes for version 1.6.5
Initial commit for Quota management in Voldemort
Workaround SystemStore bug and fix quota store inserts
Adding unit test for rate limiting
Documented minor todos for Quota management