[streaming] windowReduce added + BatchReduceInvokable reworked
Merge branch 'streaming-new' of https://github.com/mbalassi/incubator-flink into streaming-new
[streaming] Automerge error fix
[streaming] Automerge error + License fix
[streaming] CoMapTest update
[streaming] Merging with main branch and License fix
[streaming] Conflicts merged with remote streaming-new