Gametime: Bugfix, cleanup, added routes.

* Added route tracking for ships and airships in the game.
* * //gt route -- displays valid route names.
* * //gt route [routename] -- lists the arrival time for ships
* Log update wasn't always displaying day correctly.
* Some log messages were prefixed with 'gametime:' twice.
Merge pull request #351 from thatdudegrim/master

Gametime: Bugfix, cleanup, added routes