avoid an unneccessary conversion FieldLoader can do
stop pretending this is configurable and use MoveTo

fixes #5682
StyleCop
StyleCop
document for modders
new trait Parachtuable that decides on the fate upon landing
new setting to allow unlucky paratroopers
@pchote's quest against legacy truth value definitions
merge ParachuteAttachment and Parachutable
make the parachute animation optional

instead of hard-coding default sprite sequences
make the parachute palettes configurable
add a customizable parachute shadow

closes #3335
make the fallrate customizable
fix shadow sprite not being rendered on the ground
Merge pull request #5695 from Mailaender/parachute-dangers

Added the possibility for paratroopers to die on impact
Merge pull request #5814 from Mailaender/vamos-vamos

Fixed units not moving to the RallyPoint
separate content install from loadscreen
unify install from CD logic
unify music install and add a download option

closes #4759
rebase bit rot crap