Merge pull request #21 from Frank-Wu/master

initiate internal state for stateful operators
python script added for performance visualization
performance tracker update and counter added to wordcount example
wordcount example modified for cluster testing
Added performance test data copying script
Changed String UID to byte array
wc updated for testing
Merge branch 'master' of https://github.com/stratosphere/stratosphere-streaming
Started implementing Storm WordCount for performance test
Merge branch 'master' of https://github.com/stratosphere/stratosphere-streaming
Performance test scripts added
wc updated for cluster testing
Merge branch 'master' of https://github.com/stratosphere/stratosphere-streaming
performance test scripts updated
new wc source added for performance measurement
wc update for testing
Added test runner script
replaced synchronized methods with concurrent collections
performance tracker update
Merge branch 'master' of https://github.com/stratosphere/stratosphere-streaming