[Suggestion] Set default Xorg resolution to a size large enough for installer to function

[bflanagin]

Issue

Current images default to 800x600 when there is an issue with detecting the display or if the video card isn't detected properly. Unfortunately, the installer isn't designed to run at such a low resolution (and neither is Gnome) which gives users a bad first impression.

Work around

For the most part the user can go to gnome-control-center and change the display to their desired resolution once the session is started.

Possible solution

Gnome uses ~/.config/monitors.xml to control resolution, rotation, and refresh rates for individual user sessions and could be used to set a sane default for our installer.