Hide staging sites from The Hub

We have lots of staging sites and they clog up The Hub.

It's useful to have them here because we do update them sometimes, but most of the time we don't want to see them.

There should be a way to designate which sites are staging sites, which live site they are assigned to, and either filter the view to hide them or should them alongside the live site.

To be honest, the Hub needs lots more filters to make it useful for people with more than 1 page of sites.