- add multi-vehicle support: each vehicle has now a per-vehicle AirMap
  object that takes care of flight creation, traffic & telemetry
- add a base class API layer so that the interface between QGC and the
  AirMap implementation is clear, and easier to change
- removes polygon upload to vehicle (needs a better solution)

Also rename QmlPageInfo to QmlComponentInfo to cover more use cases

Also plugin'ize intrument panel PageView pages

Too complicated supporting both modes as editor becomes more complex

- You can now cancel parameter change
- Tablete friendly