Implement arrived, departed, scheduled and enroute.#1

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queenvictoria wants to merge 6 commits intofredpalmer:masterfrom

queenvictoria:master

Commits on Jul 6, 2014

Support for alerts (push notifications).
queenvictoria
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Commits on Aug 8, 2014

Implement decode_flight_route, get_last_track, get_last_track, in_flight_info and routes_between_airports.
queenvictoria
committed