Make BuyerExchangeActor to receive initialization message
Make HandshakeActor to receive an initialization message
Make PeerActor to receive an initialization message
Make MessageGateway to receive an initialization message
Make HandshakeArbiterActor to receive an initialization message
Remove wrong test

Remove "Protobuf RPC Message gateway should throw while forwarding
when recipient was connected and then disconnects" as the test wasn't
asserting that in the first place and when tried to assert that I've
realized that ProtoRPC calls don't throw an exception that can be
wrapped into `ForwardException`.
Merge pull request #114 from sortega/feature/simplify_cake

Simplify cake pattern by using initialization messages