Changed scala copyright header.
Updated license notices in in java files to be written in block comments instead of javadoc comments.
[FLINK-1110] Framework for collection-based execution
[FLINK-1110] Fix MapOperator execution and added simple test
[FLINK-1110] Implement collection-based Cross
[FLINK-1110] Implement broadcast variables for collection-based execution
[FLINK-1110] Add execution on collections for flatMap
[FLINK-1110] Add Collection-Based execution for Reduce Operators

Also fix some bugs resulting from moving stuff between packages
[FLINK-1110] Implement collection-based execution for mapPartition.

Make groupReduce code compliant with pre-java-8 versions, fix java8 tests with moved type information classes.

Fix Various warnings.
[FLINK-1110] Implement collection-based execution for bulk iterations
[FLINK-1110] Started implementing the JoinOperatorBase.

Implemented JoinOperatorBase and test cases.
[FLINK-1110] Add createCollectionEnvironment for Scala
[FLINK-1110] Implement collection-based execution for coGroup