[Ohrrpgce] SVN: teeemcee/11934 Implement 32bit -> 8bit blitting as a slow fallback to avoid BUG message

[subversion at HamsterRepublic.com]

teeemcee
2020-07-22 19:44:42 -0700 (Wed, 22 Jul 2020)
323
Implement 32bit -> 8bit blitting as a slow fallback to avoid BUG messages

This allowed deleting a number of checks for invalid 32->8 bit drawing, which is
pleasing.

The blitting is done in gfx_surfaceCopy without any dithering, because it's
just a fallback. In future when Frame and Surface are merged it can do dithering
---
U   wip/allmodex.bas
U   wip/slices.bas
U   wip/surface.cpp
U   wip/surface.h