Add README.md

Manually committed by mpyne to squash the commit sequence.

Approves and closes merge request !3

Thanks David for the solid submission including screenshots and install
instructions!
3 jobs for master in 8 minutes and 14 seconds (queued for 1 second)
Status Job ID Name Coverage
  Build
passed #430
flatpak
flatpak

00:08:14

passed #429
freebsd
freebsd kf5-qt5 qt5.12

00:01:57

passed #428
linux kf5-qt5 qt5.10

00:06:08

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