Concerning akka in osgi:
ActorRefProvider contains in akka-cluster or akka-remote bundle are not found by the akka-actor bundle, thus exposing those if required
    akka-actor and akka-osgi wrapped into one bundle (akka-osgi) taking care of the ActorSystem creation
    The akka modules reference.conf are copied inside this bundle.
    Every other akka module is imported optionnaly,
      the same for com.google.protobuf (already imported in akka-remote)
Merge pull request #985 from Crossing-Tech/osgi-cluster

Concerning akka in osgi: akka-remote/cluster ActorRefProvider exposed to akka-actor