Mallaca>Network>Packet: Add ErrorPacket
RH_Server: Add mapping between user and his socket.

NOTE: This only works AFTER the users authenticates by sending a login-command.
This command MUST be successful ofcourse.
Merge branch 'master' of github.com:JordySipkema/LD326_RH_A5

Conflicts:
	RH_Server/Server/ClientHandler.cs