Provide simple way to build and run "Getting Started Programming with Qt Quick" example

The  "Getting Started Programming with Qt Quick" example does not document how to run it with Qt Creator, and a section about this is missing.

The included .pro file just builds the custom QML plugin. The actual app should be run from the command line using qmlscene. The example also contains a .qmlproject file though that can be used for this.

Anyhow, Qt Creator does build the .pro file by default in a shadow build directory; this is best practice, and actually enforced by the Qt build system for examples (for a custom build). Anyhow, in this case qmlscene won't find the generated module.

It would be arguably easier to not use qmlscene, but to add a minimal main.cpp file for the example, so that it can be built and run in one go.