[kde-plasma] remove user-manager as it no longer exists and will therefore pull in user-manager-git and lots of other git/es2 packages

mntray is a system tray icon that displays forum announcements from rss feeds.
Very handy to notify the user about new update announcements they might want to read.

Signed-off-by: Dan Johansen <strit@manjaro.org>

Also change sddm theme on Wayfire edition.
And update some missing man-db in some editions.
Signed-off-by: Dan Johansen <strit@manjaro.org>

Signed-off-by: Dan Johansen <strit@manjaro.org>

Add back manjaro-icons package
Turn brightness when on battery to 30% instead of 50%

Signed-off-by: Dan Johansen <strit@manjaro.org>

Manjaro KDE will change theme to Breath2 in an upcoming release, so we follow that.
This also fixes the issue where window control buttons would not appear on the first opened window of the boot.

Signed-off-by: Dan Johansen <strit@manjaro.org>