Copy all file names when adding Form Class

1. Create a new Qt Widgets Application project for CMake using Creator's wizard.
2. In Projects-view, right-click on the project's name next to the hammer icon.
3. Select "Add New..." from the context menu.
4. Use the wizard that opens for creating a new Qt Designer Form Class in the project.
   This will add three files: a .cpp, a .h and a .ui file.
   After you clicked "Finish", a dialog will pop up asking whether Creator should add the path to the source files to the clipboard.
5. Click "Yes".
   Only the name of the .cpp file will be added to the clipboard.

While this is correct for the narrower sense of "source file", I think it would be good if there was an option to copy all files names because all of them should be added to CMakeLists.txt