-TextureManager now handles texture and lump names that are not properly zero terminated.

git-svn-id: http://odamex.net/svn/root/branches/texmanager@4506 b0bcef46-2027-0410-bd56-ab726e9a1d04
-Remove the numcolors field from palette_t since all palettes have 256 colors.
-Remove the numcolors parameter from V_BestColor (always use 256).

git-svn-id: http://odamex.net/svn/root/branches/texmanager@4507 b0bcef46-2027-0410-bd56-ab726e9a1d04