[FLINK-1336] [core] Fix bug in StringValue binary copy method
[streaming] StreamInvokable rework for simpler logic and easier use
[dist] Updated the assembly of the examples subdirectory

Excluded the scala example jars
Excluded the example source code subdirectories

This closes #274
[streaming] Added immutability for window and filter operators
[streaming] Make windowed data stream aware of time based trigger/eviction in tumbling window situations.

[streaming] Changed TimeEvictionPolicy to keep timestamps in the buffer instead of data-items