Added SystemBolt.
SystemBolt has one executor per worker always. It's perfect for
exporting worker related metrics data.
this section of code was moved to new PR
removed topology level stat
removed topologyPartialUptimeSecs
Merge pull request #517 from jasonjckn/system-bolt-3

Added SystemBolt.
MicroBatchIBackingMap: avoid store timeouts on multiput and multiget
Merge pull request #532 from jasonjckn/0.9.0-ibackingmap

MicroBatchIBackingMap: avoid store timeouts on multiput and multiget