Remove the ability to recall the shuttle with packets

[Garash]

Friendly reminder that spamming shuttle recalls, either manually or automatically, is *specifically* disallowed in the rules page and should be ahelped, even if it's done by an antag.

Don't prolong the round unnecessarily. If it seems like most other people want the round to end and/or you have killed most other people as an antagonist you should not try to make the round go on forever. That means that repeated recalling of the shuttle, building automatic shuttle-recall machines and not calling the shuttle after you kill everyone else on the server are frowned upon.

But I think I agree, it would be good if the shuttle recall packet was "encrypted" and could only be generated by COMMaster