Tutorial "Creating a QWidget Based Application" is not up to date

The tutorial instructs the user to manually add a newly added resource file to CMakeLists.txt. However, these days Qt Creator does that automatically. Unfortunately we cannot trivially update the documentation, because our heuristic does not add the file to the variable, as shown in the screenshot.

While I don't see a "proper" solution, I believe we can add a small hack into the cmake support that checks for the cmake variable that we use in our wizards (PROJECT_SOURCES) and adds the file there instead of to the add_executable call. This way, people following the tutorial faithfully will get the documented behavior.

In summary, the fix would consist of two steps:

1. Implement the abovementioned hack.
2. Change the wording in the documentation so that it no longer instructs the user to do this manually.

Note: Probably all other tutorials involving cmake projects have the same problem and should be checked and, if necessary, adapted as well.