added multidimension support
changed average to give average per sec
fixed the tranisent issue for DimensionTimeBucketOperator
changed the logic to calcualte the sum at every process operation instead of waiting till endwindow
removed system.out statements
removed unused import statements
Clean the kafka package in Malhar contrib project #53
fix comment
removing the elements from cache after end of window
Merge branch 'master' into site-alerts
added the test case for DimensionTimeBucketSumOperator
added test case
deleted test apps
restoring log4j
Merge pull request #75 from gauravgopi123/issue-52

[Issue 52]: addCombination doesn't work in DimensionTimeBucketOperator
Merge branch 'master' into mrapplication

Conflicts:
	demos/src/test/resources/log4j.properties
	library/src/test/java/com/datatorrent/lib/logs/MultiWindowDimensionAggregationTest.java