Support for using any number of CRTC:s in any number of screens

Signed-off-by: Mattias Andrée <maandree@operamail.com>
Base gamma adjustment on the gamma ramps at startup

Signed-off-by: Mattias Andrée <maandree@operamail.com>
Be helpful about screens versus CRTC:s: suggest CRTC if only screen 0 exists, and suggest randr if using vidmode in such case

Signed-off-by: Mattias Andrée <maandree@operamail.com>
Merge branch 'master' into multimonitor
Merge branch 'multimonitor' into preserve-calibs
Merge branch 'multimonitor' into screen-vs-crtc
merge preserve-calibs

Signed-off-by: Mattias Andrée <maandree@operamail.com>
Merge branch 'screen-vs-crtc' into future