Cleanup code of SimpleServer/SimpleClusterServer
Packet only deal with plain json string, let business logic choose which
json decoder/encoder.
Merge branch 'master' of github.com:wandoulabs/spray-socketio
Synced with EventPacket
Merge branch 'cowboy129-master'

Conflicts:
	src/main/scala/spray/contrib/socketio/Namespace.scala
	src/main/scala/spray/contrib/socketio/examples/SimpleClusterServer.scala
	src/main/scala/spray/contrib/socketio/examples/SimpleServer.scala
	src/main/scala/spray/contrib/socketio/examples/benchmark/SocketIOClusterTestServer.scala
	src/multi-jvm/scala/spray/contrib/socketio/SocketIOClusterSpec.scala
Allow construct event packet with args: String*
cleanup
Overload EventPacket's args json string to condictions of A. one single full json string and B. Seq of each arg json string.
Updated example code.
Renamed ConnectionActiveSelector to ConnectionActiveResolver
Do not need a special ConntionActiveResolver, use plain actor is enough.
Pass multi-jvm test