Reply with reference so that the client can store it ASAP

I am pretty sure that it ok to reply with the StreamRef as soon as possible, so that the client can store it to filter messages by StreamRef/Server (for example this is needed by Spurs) and then continue processing everything. I do not have a big experiencie with reply and gen_fsm, so I want to check that is ok. At least it is working.

@elbrujohalcon comments?