[Feature Request] Mute/Unmute Switch Node

Sometimes a chunk of a workflow doesn't need to run, but it's still desirable to keep it in. But its placement or number of nodes makes selecting them problematic for a mass ctrl-M.

When the mute switch is placed, it creates a line and everything to the right ("downstream" for the graph) is muted when it is toggled on.

options:
* Bonus points if it draws a line across the window
* an area, or multiple ones, can be created by ctrl+drag to create irregular shaped zones of quiet.
* a "set" button that remembers every selected node when it is used. All those nodes are muted/unmuted with the toggle.