Opening CMake project creates duplicate kit

1. Create a new CMake-based project using the wizard for "Qt Quick Application - Empty".
2. Build the project.
3. Close the project.
4. Delete the project's CMakeLists.txt.user file.
5. Open the project again.
   Creator will create a new kit which duplicates the kit you built with in step 2.

Creator should detect that the existing kit matches and not create a new one.