Diagram Editors: Display context menu entries from the ContextMenuService

Display context menu entries from the ContextMenuService in diagram editors.

Testing instructions:

1. Open any component architecture
2. Perform a right-click to any component
3. Observe: The context menu contains the menu items from the context menu service such as "pack component"

Follow-up question: Schould there be a restriction to what elements are actually displayed? The entry "reveal in editor" does not make sense in an editor, for example...