Adding references where applicable, as removed by 023a818738d64da01ebecc5d4a26356055ba0021 when removing stale example. Add example run snippet to the example landing page. Remove stale example qdoc file that is superceded by current example. Task-number: QTBUG-69191 Change-Id: I62dc66edc86da5efb4c79fd124edb2fa619aeb6b Reviewed-by: Topi Reiniö <topi.reinio@qt.io>