Shuttle Travel (Beta)

# Description
Implements ticket purchasing, ticket collectors, and shuttle travel (scene transfers).

# Known Issues
These are a few issues I have gathered/observed, some directly related and other indirectly to the TravelService. The major issues seem to be more pronounced when there are multiple clients, or for clients which have been logged in for an extended period of time/has traveled multiple times. Tackling the major issues is my next priority.

## Major
* The movement counter unexpectedly gets out of sync. Once the counter has caught up, this can lead to behavior such as "self deleting" (if the character has moved outside their own viewing box) or teleporting characters. Happens quite variably.
* While loading, sometimes clients will get stuck at "Loading Objects..." For now, simply pressing "esc" and re-zone. Happens quite variably.

## Minor
* Tickets can be used while the shuttle landing animation is still playing.
* Due to the default 1m x 1m bounding box size of shuttles at the moment, an "out of range" system message will be produced for some locations; this seems to be more predominate for the smaller shuttleports where the ticket collector is farther away from the shuttle. For now, just move closer to the shuttle and retry.

# Notes
* All tickets costs are zero for testing.
* Tickets currently are set NOT to persist to the database.