replace implementation of data-controller-singleton

The singleton is now a leaking singleton, which means that it's
destructor is not called when the programm exits. This works for now to
remove a segfault but should be cleaned up later.
Merge branch 'master' of github.com:CVVisualPSETeam/CVVisual
Merge branch 'master' of github.com:CVVisualPSETeam/CVVisual