Packet String Improvements

[Mako88]

So here's the changes I'm thinking packet-wise (let me know what you think): When a client hosts a game (packet 21), they will recieve back 21GameID with the GameID of their game. When they want to unregister a game they'll send 22GameID with their GameID to unregister (the tracker will check both the port/IP their sending from AND the GameID they send to makes sure that a host can only remove his own game. This should make it impossible for someone to spoof an IP/port to remove a game since they'd also have to know the GameID of the game to remove).

When the tracker recieves 22GameID, it will reply with 22-0, 22-1, or 22-2. 22-0 means the game unregistered succesfully. 22-1 means the GameID wasn't found (or didn't match the IP/Port), and 22-2 means the IP/Port wasn't found (or didn't match the GameID). (This could be simplified to just 22-1 for success and 22-0 for not-success if you'd rather).

When a client sends 26GameID to hole punch, if the GameID isn't found, it will recieve back 27GameID (the ID of the game they tried to hole punch).

Finally, if a host is updating a game, he will include the c=GameID key in the value string so that the tracker knows it should be updating. Otherwise, it will create a new game. (So for instance, if the tracker gets 21b=HEADER,z=BLOB, it will create a new game, but if it gets 21b=HEADER,c=GameID,z=BLOB it will update the game with GameID). This will also be double checked by both IP/Port AND GameID to prevent abuse.