surfaces added first are part of the map itself
it's better to drop e.g. some plasma cells rather than e.g. entire walls
it's also less error-prone to work with since we don't need to fix numbers on read
but only check on write in exactly 2 spots
also removed tr.shiftedEntityNum because it was unnecessary...
use the "premake" tool from the cnq3tools repo with
"--quake3dir=<q3dir>" to generate a VS sln and gcc makefiles
this changeset also removes the "clever" handling of fullscreen/windowed
changes which didn't actually work and just broke windowed mode