live-config: linstallersession: ensure we redirect to /dev/null update-alternatives' output.
live-config: linstalleralan: still needs work, but while waiting for workarounds on alan2's side, at least make it not fail.
glade frontend: made Service.return_color() return the light variants of the head_col.
modules/fstab: inst: configure zramcfg if we should.

The module now supports the new setting "zram": if True (default),
zram will be configured, if the physical memory is less than 2048 MB.
Currently is not possible to tweak the limit in the user-side, unless
by manually editing the ZRAM_LIMIT variable at the top of the module.
Release 5.23.0