Feature Request: Reverse expand button for parents or children

[ErikKoppenhagen]

By clicking on the expand button in the top right corner of an element/view, all children are expanded. It would be nice to have to oppising funtion, too: close all children. This would make the work with the diagram view a lot easier.
Additionally, there could also be a button to close all other parents. It would be similar to the magnifying glass, but you still could see the context you are in.