In 2007 in ioquake3 unified-sdl branch (revision 1144) setting
r_colorbits in q3_ui was removed but the Color Depth menu option was
still kept. Setting r_colorbits was not removed from the Team Arena UI.
In 2011 I removed the Color Depth menu option from q3_ui as it did not
change any cvars. Yesterday I restored the option not realizing this
and thinking that requesting 16-bit color depth worked.
Add setting r_colorbits back to q3_ui so Color Depth menu option works
again. I changed Color Depth options 'Default' to reset r_stencilbits
instead of 0 and '32 bit' to use r_stencilbits 8 instead of not changing
the value.
However I discovered r_colorbits 16 does not actually work on my system
(Debian Jessie x86_64 nvidia). ioquake3 was reporting the requested
value instead of the actual obtained value. Fixed in my previous commit.
61404e25c4