gui bugs fixed

checks don't push all of the content to the left when they appear.

This can take up to 8h on some of our test machines with slow
HDDs... don't make it mandatory.

We want to avoid seeing squashfs errors here..

This is taken care of when installing grub and it's using the proper
grub_distributor variable.

of the upper left corner.

the 'primary' menu, not submenus, so the continents are one menu, zones inside each
continent in the other.

- Format label text in menus to replace underscores with spaces.
- Fix floating time label position code to keep it inside the map boundaries (when
  extreme southern zones were selected)
- Pad the left and right edges of the map to match the content borders of other
  installer pages.
- Update the current time in the floating label  when a timezone is selected from
  the menus.

Avatar selection was removed

NVME devices don't follow the standard naming scheme, the device
itself ends up with a number and there's a "p" in between the device
name and the partition number.