CMakeProjectManager: Files wizards are disfunctional

Steps to reproduce:

• create a Qt widget application from template use CMake as build system
• add a Qt Form Class to this project

Current result:

• the wizard is incapable of adding the created files to the CMakeLists.txt
• instead it offers to copy the file paths to the clipboard
• when using the content of the clipboard to modify the CMakeLists.txt it reveals that it only stores one of 3 files

Note: Qmake and Qbs based projects work as expected..