[ros-general] Freeldr UI modifications

[mf]

Hi,

I recall having heard several suggestions to make freeldr easier on the
eyes (don't underestimate 60Hz VGA resolutions on a CRT) and/or make it
look more familiar to ntldr. I have experimented with editing bootsup.c
and the result implements both suggestions. The black background makes
it less flickery on CRT displays and looks more in line with ntldr (the
Windows boot loader). Please see the attached image and tell me your
thoughts and observations.

Best Regards,

mf.