* restructured some code that could not be converted as-is due to access to data that should be off-limits to scripts.
* exporting most of PLAYER's member fields.
* Remove unused `getincanglef()`.
* Remove unused `getincangleq16()`.
* In `PlayerHorizon` struct, clamp value when setting target in `__settarget()`, not each public `settarget()` overload.
* Rename `PlayerAngle` method `applylook()` to `applyinput()`.
* Rename `PlayerHorizon` method `sethorizon()` to `applyinput()`.
* In `PlayerHorizon::applylook()`, slightly clean return to centre code so it doesn't do math if already at 0.
* In `PlayerAngle::applylook()`, slightly clean rotscrnang/look_ang code so it doesn't do math if already at 0 and reposition where mouse input is applied so that if input is applied, the player never enters a spin.
* In `Duke3d::player_struct::apply_seasick()`, use `buildfang()` method instead of scaling float to BAM within function.
Aside from not having been functional, this is ultimately more harmful than useful as it forces loading of a large number of textures at the same time during gameplay instead of spreading them out.
* Added in fca846272e to deal with signed adjustments but its just not needed.
* Made better use of `binangle`/`fixedhoriz` class getters and setters than before as well.
After discovering yet another misbehaving place in the game I think it can be safely concluded that this is better left off unconditionally.
The only remaining place where this still gets checked is in nnexts, but I wouldn't expect this to work either.
Fixes#292
It is totally unclear what happened here in the original code, but the info apparently never reached the place where it's being checked. BloodGDX just ignores it so we do now, too.
