Partial track list and lookup support

Adds very basic mapping from track IDs to station IDs on the CTA rail
system, with more still to come for track numbers, rail movements, and
available services.

Also begins to make the use of 'id' and 'key' consistent, preferring the
former, with some additional updates to phrasing.
Consolidated route aliases

Cleans up the static CTA routes with pattern branching where possible.