Ported survival02 to lua and added general polish

What this PR does:
- Ported survival02 to lua
- Added a lua functions for airstrikes (spyplane, parabombs)
- Added a lua function for paratroopers and replaced the "old paradrop methods"
- Removed "Facing: 0" on actors that don't use facings and "Health: 1" as it's default in all map.yaml files
- Updated the legacy map importer in order to omit above values while importing
- Reordered all named actors; now they're at the end of the "Actors" list
- Increased ant health on the shellmap. They have a better chance against the allies now. :)
- "Disabled" messages like "xyz30 changed map difficulty to ."
- Added all speech notifications to notifications.yaml

Still to do:
- [ ] Teach the lua-c# bridge how to use nullable types (WPos?)
- [x] [This](https://github.com/abcdefg30/OpenRA/commit/be6cb0537635f5aae7f11caf93db310213d45572#diff-61cd027831d09aa05e113bf2de1593a4R149) doesn't seem to be done correctly, I'll have another look at it -- *should be fixed now*
- [ ] Soviets are killed by their own mines
- [ ] Add guards for the soviet harvester
This is bogus.  Cache the traits in the constructor instead.