Better directory structure

See merge request STJr/SRB2Internal!321

Support W_VerifyFile on PK3

See merge request STJr/SRB2Internal!328

Timerres fix

Closes #213

See merge request STJr/SRB2Internal!338

Use byteptr.h macros in flats png

See merge request STJr/SRB2Internal!339

Pain sound fixes

See merge request STJr/SRB2Internal!335

* Fix native MF_PAIN sound extension being limited to UINT8 range, which only became evident when the new s1/2/cd/3db/kc sfx were added.
* Make the pain-causing cactodes have DMG_SPIKE.

Correct location of MT_CACTI10 and MT_CACTI11 in relation to their positions given in info.h and dehacked.c (fixes several ACZ-related crashes)

Patch blending aggregate return fix

See merge request STJr/SRB2Internal!333

Revert "Merge branch 'gl_skydome' into 'master'"

See merge request STJr/SRB2Internal!331

This reverts merge request !326

More harmful cactus

See merge request STJr/SRB2Internal!329

Lots of death stuff

Closes #207

See merge request STJr/SRB2Internal!306

Clean up an ungodly amount of shit relating to abilities.

Closes #195, #167, and #177

See merge request STJr/SRB2Internal!307

Lua save-banks!

See merge request STJr/SRB2Internal!295

Fix the V_DrawCroppedPatch bleeding on the current charsel screen.

See merge request STJr/SRB2Internal!311

PNG patches

See merge request STJr/SRB2Internal!327

Always force player camera direction for springs with horizontal thrust component.

See merge request STJr/SRB2Internal!330

New EXE icon

See merge request STJr/SRB2Internal!265

I_Error if no frames are found for a loaded skin's SPR2_STND subspriteset, given this is what everything will default to if nothing else is provided, and I really don't wanna go across the code adding checks for sprite2s not existing (since R_GetSkinSprite2, under all circumstances other than this one, is capable of bouncing back).

Also allows them to be used as sprites.

Increase maximum number of Luabanks to 16 on Steel's suggestion. (Using the Web IDE 'cuz I'm tired, so no new exe; luckily I made the code flexible to constant replacement!)

Follow-up fixes for reset-upon-dying music

See merge request STJr/SRB2Internal!284