Dead stations do not allow docking. Should fix oddity reported by Wyvern Mommy in Nova mission.

git-svn-id: http://svn.berlios.de/svnroot/repos/oolite-linux/trunk@5677 127b21dd-08f5-0310-b4b7-95ae10353056
Padding on parcel contracts still wasn't quite sufficient for really short trips, which could expire before you got to the station. Add four hours to deadlines.

git-svn-id: http://svn.berlios.de/svnroot/repos/oolite-linux/trunk@5678 127b21dd-08f5-0310-b4b7-95ae10353056