* Move the misc types in the file to bottom, so that ATTRPACK at least is usable for RGBA_t
* Include endian.h, so that UINT2RGBA can be defined correctly for big endian builds
* Add more comments to make clear the main sections of the file

Remove FUNCMATH from functions with a void return value or args, or examine variables other than their args (which could be modified)

D_PostEvent_end is only used by Allegro (used by the DOS port) to help timers work, so check for PC_DOS in preprocessor code. Also remove FUNCMATH from said function.

P_NullPrecipThinker no longer should have FUNCMATH (though I'm not sure if it should have had it in the first place anyway)

File loading hotfix

See merge request STJr/SRB2!310

Make sure handles of files opened by W_LoadWadFile are closed if we abort loading the files for whatever reason.

ESPECIALLY if the file is already loaded in SRB2, that's just silly.

Patch offsets fix

See merge request STJr/SRB2!305

MI minor refactoring

See merge request STJr/SRB2!294

Multi-patch texture support for transparency AND translucency

See merge request STJr/SRB2!293

now that V_FLIP's effects are always supported in V_DrawFixedPatch, there's no need for the "flip" variable anymore

HWR_DrawFixedPatch: Add V_OFFSET support for V_FLIP in hardware code as well, also add missing SHORTs for gpatch fields

Make V_OFFSET no thing without V_NOSCALESTART, to remove any potential glitches with using it on its own

mapheader lua unarchive hotfix

See merge request STJr/SRB2!302

Music Code Cleanup

See merge request STJr/SRB2!278

Handle fix for SDL Mixer

See merge request STJr/SRB2!301

More accurate GIF delay

See merge request STJr/SRB2!276

MI's unimportant code cleanup

See merge request STJr/SRB2!295

I've voided this out on other sound interfaces than SDL Mixer ones because I'm both not sure whether they need it, and not sure how to make them work with it if they do.

Remove "playerdeadview" variable; it's not been used for its stated purpose for who knows how long now

Besides rankings popping up when you die just sounds weird anyway, maybe I'm just used to SRB2 not doing it I guess

Remove unused ObjectPlace_OnChange prototype (from when Objectplace was a consvar, which it is not anymore)

Also corrected what appears to be a typo in some comments above?

(it's only set to 0 in software, and only ++'d in OpenGL, what kind of sense does that make?)