Allow to edit multiple selected resources of my cluster in a single multi-resource document/editor

[adietish]

Currently one can only edit individual resources: select a pod in the resource tree, pick "Edit..." in the context menu. As soon as you select several resources, you dont have "Edit..." in the context menu any more. It would be nice to be able to edit those in a multi-resource document. Alternatively one could also open several editors for each of the selected resources.