spearmint: Improve texgen/tcGen warnings
spearmint: Increase max images supported by animMap

Q3 supported up to 8 images for animMap. Increase it to 64 to handle
other games. I also make it dynamically allocated like JA.

(Though my implementation is based on Q3 handling of texMods, not the JA
implementation.)

RTCW/ET use and support up to 16. JA uses and supports up to 32.

FAKK has shaders that use 47 and 19 images.
EF2 has shaders that use 47, 40, 10, and 9 images.
SoF2 has one clampAnimMap that uses 38 images.

I didn't check if those games actually support that many images though.