Lunch train

## Lunchtrain
- `!lunchtrain new <time> <destination>` - Create a new lunchtrain.
Time must be in 24 hour format. (13:00)
- `!lunchtrain list` - List currently scheduled trains.
- `!lunchtrain join <id>` - Join the specified train. Id's are 5 digit
hexs and can be viewed via `!lunchtrain list`