Implement the PilotEdge Datarefs

[kuroneko]

When PilotEdge forked libxplanemp, they also implemented a tonne of extra datarefs.

Whilst we can't/won't support all of them in XSB, we should implement them so there's only one next-gen CSL target.

Details of the PilotEdge datarefs are at http://www.pilotedge.net/pages/csl-authoring

[TwinFan]

I've just done that in my fork with commits TwinFan@89adfaa and TwinFan@76a57b0, as an add-on to implementing my issue TwinFan/LiveTraffic#143, which also includes changes to LiveTraffic and a script, which migrates CSL's .obj files, as a temporary solution to the shared dataRef problem when several multiplayer clients are running. The script is updated to migrated some world_traffic dataRefs to their new counterparts in libxplanemp.
Feel free to take over parts of it. My fork contains a number of other changes, which I believe are backwards compatible, but probably require discussions, which is why I don't enter a pull request for the entire thing now. But I could if you like.
I came across this issue here only when starting to document the new dataRefs.