Merge pull request #2 from russel/rafał-remote-actors

Upgrade Groovy and Netty to latest versions.
Updated NettyServer test
Non-blocking NettyClient. Test refactoring.
Netty Client-Server communication test
Netty Client-Server communication test
Register Actor
Removed LocalNode and RemoteNode
Removed LocalNode and RemoteNode. Added RemoteActorFuture
Removed LocalNode and RemoteNode. Added RemoteActorFuture