Filter out arrivals / departures with negative ETA

[lanami]

Exclude arrival infos where ETA < 0 from Alexa's announcements (this indicates arrivals and departures which already happened).

[coveralls]

Coverage increased (+0.4%) to 55.048% when pulling 0dee575 on lanami:84-filter-departed-arrivals into 7e5c265 on OneBusAway:master.

[barbeau]

@lanami Thanks for working on this! I'd like to see this as an option that users can turn on and off. For the OBA mobile apps, some users like knowing when they just missed a bus, while others only want upcoming arrivals. Default should be including negative ETAs. Feel free to propose intent and exact keywords.

[barbeau]

Closing and re-opening this to trigger the new ICLA bot (hopefully).

@lanami You'll need to sign the ICLA again, which the bot should hopefully link to in it's comment.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[coveralls]

Coverage increased (+0.4%) to 55.048% when pulling 0dee575 on lanami:84-filter-departed-arrivals into 7e5c265 on OneBusAway:master.

[lanami]

Will do