usabart: Bring in usaebart and OAK shuttle

[Nagamasa]

BART is currently split into 3 different systems:

• the main wide-gauge 5-line service
• eBART, standard guage DMU extension of the Yellow line
• OAK Connector AGT shuttle to OAK/li]
  

All of these are mapped as equals on the BART System Map: https://www.bart.gov/system-map, I don't think we should be splitting it up here into separate systems based on the infrastructure provided. Proposal is to consolidate usaebart into usabart and move OAK Connector out of usaair into usabart.

[si404]

I'd support moving eBART into BART and reducing by a system (though I'm also open to keeping it separate as its a somewhat different thing*). But the Oakland shuttle doesn't remove a system, and means it's missing from the other similar routes.

Plus the shuttle is not given a colour. If it was 'grey line' or something, then that's treated as equal. It's not even given a letter.


*But, where these transfers to non-electric trains happens on Metro North and the LIRR, we've treated it as one route, rather than a separate bit.