Add the proper dependency to Scala 2.11 (sources) form SDT

Fixed #1002290.
New ScalaReconciler implementation that listens to activation events, like the Java one.

Fixed #1002215
Merge pull request #825 from dragos/issue/scala-reconciler-listeners-1002215

New ScalaReconciler implementation that listens to activation events, like the Java one
Merge pull request #826 from dragos/issue/missing-sources

Add the proper dependency to Scala 2.11 (sources) form SDT