Merge pull request #11 from nathanmarz/master

merge changes from nathanmarz/storm master
Merge pull request #12 from nathanmarz/master

merge changes from nathanmarz/storm master
TaskMessage enhanced to enable null payload
Merge pull request #13 from nathanmarz/master

merge changes from nathanmarz/storm master
enable Java HashMap for zmq messaging
restore TaskMessage.java
Merge pull request #580 from anfeng/master

Enable java HashMap used for ZMQ messaging configuration