Is there a way to disable all functions in a deployment slot?

Is there a similar setting to `WEBJOBS_STOPPED` that can be turned on and it'll disable all of your functions from running? My project is node based if that matters.

I'm trying to change my deployment process to use a deployment slot, auto swap, and zip push. I'd like to turn the functions off in the staging slot once this is working. I could setup a secondary storage account for the staging slot, but since this is just a deployment target for auto swap it'd be much easier to just turn them all off with a slot setting.

I also don't want the old version of my functions running along side the production version post swap. For my web apps I set `WEBJOBS_STOPPED` to `1` in the staging slots but that didn't seem to do anything for my functions app.

The issue names no repository files, tests, or implementation entry points. Start by tracing how WEBJOBS_STOPPED and deployment-slot settings are handled for Azure Functions, then compare that behavior with the staging-slot auto-swap and zip-push flow. Done would mean a clearly supported way to prevent all functions in the staging slot from running.

Written by the indexing model from the issue text.