error statistics on controller side
move ErrorStatistics.java to cosbench-core fold
remove the target infomation from operator and storage
Merge branch '0.4.0.1' of https://github.com/xiaoerlyl/cosbench into xiaoerlyl-0.4.0.1

Conflicts:
	dev/cosbench-controller/src/com/intel/cosbench/controller/model/WorkloadContext.java
Merge branch 'xiaoerlyl-0.4.0.1' into 0.4.0.1
Merge branch '0.4.0.1' of https://github.com/intel-cloud/cosbench into 0.4.0.1