Login system rework

[Codestech1]

Description

Current handling of the protocol state needs to be reworked. Currently plugins can send packets at any time without handling client response or waiting to it. This is incorrect implementation and always when the server sends a request it needs to await for the client response if there is a response packet available to a specific action. This should also fix the problem with setting up compression without need to send the compression setup packet at beggining. The new system is also expected to provide a way for setting up encryption.