SPR2_DKRT: A new SPR2 which allows character WADs to define a unique kart explosion husk

See merge request KartKrew/RingRacers!55

Minor action special / ACS built-in fixes

See merge request !58

COM_Exec_f: By default, insert into command buffer

Closes #281

See merge request !56

This could be done with Get/SetLineProperty just fine, but added just for completion's sake -- the Hexen instruction set is now fully implemented, minus SoundSequence which is for a feature we straight up don't have.

Instead of using a linedef executor tag as an argument, apply an action special to the angle manager object that you had to place anyways.

There is no UDMF version check because the old behavior was practically unusable.

- Resolves #281 under standard operation
- Add `-immediate` parameter for previous, `wait`-ignoring behaviour
    - Used by configfile, EXECCFG

Fixed the p->player null check in destroyed-kart.cpp being a part of hasCustomHusk rather than being a part of pValid as it's supposed to be

With the help of GitLab user Lach, I turned my approximated sprite scaling in destroyed-kart.cpp into 100% accurate sprite scaling

Changed float percentage mathematics in destroyed-kart.cpp into approximated fixed mathematics that will not risk a desync across platforms with different float standards

Revert "I've spent the last 3 or so hours just trying to get a feel as to how to even begin approaching this task but I think it's just way beyond my understanding, I don't have enough experience with big C / C++ projects to know if its just me or if this project being 2 decades running makes it a freak of nature but I'm just barely holding on here and not seeing any results, so nuts to it for now."

This reverts commit 6125572b.

I've spent the last 3 or so hours just trying to get a feel as to how to even begin approaching this task but I think it's just way beyond my understanding, I don't have enough experience with big C / C++ projects to know if its just me or if this project being 2 decades running makes it a freak of nature but I'm just barely holding on here and not seeing any results, so nuts to it for now.

Workaround for Egg TV replay deletion bugs

See merge request !54

Fix random desyncs with `-file` in addons with custom net cvars.

Closes #47

See merge request !29

Clean up Profile setting in edit menu flow (#34)

Closes #34

See merge request !51

Skincolor Fixes (#109, #115)

Closes #115 and #109

See merge request !50

Expose most of the music handler to Lua

See merge request !41

Expose render splitscreen to lua

See merge request !38

Expose clip rect functions to lua

See merge request !39

based on toaster's suggestion

As per suggestion by Sal

Reduces the number of unique places to update when adding new ones

Prevents changing player skin/color cvar when backing out (resolves #34)

Minimap directioning dot will use the correct skincolor even when set up for alternate remappable indices

Resolves #115

Resolves KartKrew/RingRacers#109

My mistake gomen

Expose follower array and follower_t to lua

See merge request !42

Disallow palette flashes with reducevfx

Closes #214

See merge request !48

Fix SIGSEGV related to GL renderer

See merge request !49

From V_DrawFixedPatch function call.

exposed ply.startboost and the absent BT_ flags to lua

See merge request !32

Fix unflipped important objects & elements (also fix trick treshhold when flipped)

See merge request !28