Corrects possible null point expception in blockOnPowerStateChange
TA47199: temporary alteration to process new instanceRange extraConfig value and translate that into minInstance value
TA45116: immediate acknowledgement of serengeti limit instruction
S31830: adds skeletal outline of unit tests for ssh connection cache
S31830: corrects null check in hadoop connection to check dns name instead of ip address
S31817: adds user level logging to vhm.log for all logged VC events