MFG Akka-Stream-Extensions

Version 0.11.2

Add a Debounce graph which wrap elements in Ok or Ko depending on whether they are the first occurence in the given time window.
Add Flow.debounce which keep only the fist occurence of an element in the given time window.

Version 0.11.1

Fix tut-plugin bug which added tut-core to the POM #28.

Version 0.11.0

Add cross compilation for scala 2.11.11 and 2.12.2 #26
Upgrade dependencies
Remove deprecated :
- SinkExt.collect use Sink.seq
- SourceExt.fromStream(InputStream) use StreamConverters.fromInputStream
Deprecate SourceExt.unfoldPullerAsync, use Source.unfoldAsync
Rewrite EsStream.queryAsStream using Source.unfoldAsync
Switch some dependencie to Provided (you need to specify those, they will not be transitively pulled)
- In akka-stream-extensions-postgres : "org.postgresql" % "postgresql"
- In akka-stream-extensions-elasticsearch : "org.elasticsearch" % "elasticsearch"