QML port of fonts kcm
Summary:
port the fonts kcm to QML, reviving an old branch.
UI based upon M112/411
make use of the new Kirigami FormLayout
depends from D8641
Fixes T7244
Test Plan: tried all the options
Subscribers: hein, ngraham, plasma-devel
Tags: Plasma
Maniphest Tasks: T7244
Differential Revision: https://phabricator.kde.org/D8916