Follow up Jira to RT-19968 "Document that Platform.runLater must not be called before FX is initialized"

The comments around application runtime initialization (in Platform.runLater) seem like they belong more properly in the application lifecycle javadoc for the Application class rather than on the Platform.runLater method specifically.

Kevin Rushforth advises:

"One possibility is to have most of the documentation in the Application class, and then refer to it from Platform, JFXPanel, and FXCanvas."