Fix Lua warning when accessing custom field on mobjinfo

Closes #1043

See merge request STJr/SRB2!2034

Fix segfault when trying to set a read-only field on player_t

Closes #1041

See merge request STJr/SRB2!2032

Colors Ultimate

Closes #745 and #496

See merge request STJr/SRB2!2027

Implement per-texture offsets in UDMF

See merge request STJr/SRB2!2018

- Swapped invcolors of new character skincolors
- Renamed Stone to Meteorite & changed text color to gray
- Tweaked some colors' invshades

- Replaced Mindaro with Goldenrod
- Changed Topaz, and fixed inconsistency with its placement
- Small tweaks to Kiwi, Seafoam, Noble and Sangria
- Changed other NiGHTS link colors a little (& removed old iterations)

- Renamed Amethyst to Crystal
- Moved some of the new colors
- Tweaked a couple of invshades

- Added 6 new colors to match Chaos Emeralds
- Changed Taffy & Sapphire (3rd emerald)
- Renamed old Emerald to Shamrock

- Changed Bronze
- Added Boulder & Volcanic
- Tweaked Galaxy

- Tweaked Bubblegum
- Added 8 new colors by Alice
- Added 22 new colors by sphere

Lach authored 2 years ago and sphere committed 1 year ago

- Tweaked Orange and Cobalt
- Added Pepper, Jade, Headlight, Master, Mauve, and Taffy
- Fixed Mario mode invincibility color cycle
(Opposite color shades are placeholder for now)

Optimize field lookups in Lua metatables

See merge request STJr/SRB2!2024

Fix segfault when ghost dies from a death pit

Closes #999

See merge request STJr/SRB2!2026

Interpolate Models when Scaling Mobjs

See merge request STJr/SRB2!2021