Monitor hotplug support, this fixes issues with monitors on DP-MST
docs sometimes not lighting up (rhbz#1652279)
Adding support for using the firmware's bootsplash as theme background
New bgrt theme which implements the boot-theme design from:
https://wiki.gnome.org/Design/OS/BootProgress
Including the new theming for offline-updates shown there
Make the bgrt theme the new default and upgrade systems which are using the
charge theme, which is the old default to use the new bgrt theme
Cleanup the spec-file a bit:
Remove unused / unnecessary %global variables
Sort the sections for the various plugins and themes alphabetically
Simplify theme filelists
