GTFS-RT > trip updates static<>real-time matching & tests

[mmathieum]

• implement trip Ids OutOfSync boolean
• in makeCache...() function, extract filtering all trip updates in testable function
• create a map of real-time to static trip ID for when they are out of sync
• only try fallback trip IDs matching if out-of-sync
• try using start_time (only when route_id is provided to avoid iterating over all trip updates)
• then match using stop_id and/or stop_sequence
• ...