Add TrimTripsOutsidePolygon strategy

[tisseo-deploy]

Summary:

GTFS Transformer: Add a new strategy to trim trips using a WKT geometry.

Expected behavior:

This strategy applies the trim trip strategy using a WKT Polygon or Multipolygon.
It should remove all stop_times from stops outside the polygon
Need one argument named 'polygon' using WKT format and WGS84 (SSID : 4326).