Redesign of system monitor plasmoids

Summary:
Those plasmoids are intended to replace the old systemmonitor plasmoids
They are based upon the new ksysguard daemon: see D28333 and D28141

It has pluggable presets and sensor "faces" which are available from the KDE store

Every preset is available as a separate plasmoid.
By default are installed ones to replace
roughly one by one the existing systemmonitor plasmoids so systems that use it
will get the new ones in the updates

Depends on D28922

Test Plan: {F8209642}

Reviewers: #plasma

Subscribers: alexde, ngraham, davidedmundson, mmustac, ahiemstra, plasma-devel

Tags: #plasma

Differential Revision: https://phabricator.kde.org/D28487