Port to QDoc
This project is a bit iffy to port to QDoc:
- there's no top-level library target to have a global qdocconf and consequently index page
- there's no library for org.kde.kquickcontrols, it's just a bunch of INSTALL() calls
Related metatask: teams/documentation/sprints#45
How to build the docs: teams/goals/streamlined-application-development-experience#10