Terbs weekly fun #6: New random event: Shuttle Loan

- Centcomm asks to borrow the shuttle for a while (not much longer than standard shuttle trips). Players have to choose to accept the offer. 
- The shuttle is being borrowed for a randomly chosen purpose, which results one of the following (announced to players before they make the decision): 

>- The crew have to kill a team of basic syndicate NPCs, and get a specops crate + 100 supply points as reward. 
>- The crew have to kill a small number of russians + space bears, as well as a russian with a mateba, and get a party crate + 100 supply points as a reward. 
>- The crew have to kill a small group of giant spiders (with a nurse spider) and get space ninja shoes +  a spec ops crate + 100 supply points as a reward. 
>- The crew get 9 predefined department-related supply packs. 

See commit log for more details.