Add service change/interruption information

[jonthornton]

Possibly use http://web.mta.info/status/serviceStatus.txt ? This would be challenging because the text file is barely structured and will require significant parsing.

[FranzLiebkind0]

Has there been any interest in using the MTA "subway alerts" JSON feed on MTA Developer Resources? I think these are new since this open enhancement was posted in 2014