Add an image and a QDoc file, remove the (in some cases misleading)
doc comments from the CPP sources, group the slots all together in the
source so as to document them together, group the two private methods
together. Dust the header lightly with comments to classify the class
members and enclose relevant parts in QDoc snippet markers.
Task-number: QTBUG-111228
Pick-to: 6.5
Change-Id: I0090fb45ce8d5a8f168fde9b3247d541b709c1b2
Reviewed-by: Andreas Eliasson <andreas.eliasson@qt.io>
Reviewed-by: Ivan Solovev <ivan.solovev@qt.io>
f2ab85429d