[Draft discussion] Routing more than 4 Channels of Audio to Plugins

@N9R I have reviewed the description introducing only small changes. Looks very good to me, and if you or anyone else have no objections I’m happy to promote it to #features in 24 hours.

This areas is out of my depth. Just in case, are there any connections between this request and these other?

I’m only asking to check whether it makes sense to link them to each other (and if so, why).