!osg, pro Updated OSGi dependencies and using a BundleDelegatingClassLoader

* Numerous version upgrades to dependencies
* Publish integration test maven dependencies automatically
* Use slf4j logging, with standard OPS4j Pax Logging
* Maven and sbt use different target directories
* Add a custom serializer to the integration test
* Add akka-persistence to the integration test
* Removing reference copying and using a BundleDelegatingClassLoader
* Make akka-actor a proper bundle, and remove duplicate classes and
  reference.conf files from akka-osgi
* Remove akka-osgi-aries

This is a hackathon team effort by:
* Björn Antonsson
* Endre Sándor Varga
* Roland Kuhn
* Patrik Nordwall