Feature: multi-tenancy with custom domains for each Team / Organization

[evereq]

See https://github.com/vercel/platforms and check https://platformize.co/platforms-starter-kit. Basically, with help of NextJs / Vercel deployment, we can host Ever Teams on different subdomains, way that each team gets its own subdomain to work with which later can be mapped (CNAME via DNS for example) to totally custom domain!

For example, let's say some COOLTEAM registered in https://ever.team and we automatically assign to them a custom domain (can be paid feature!) like cool.ever.team. Next, they map it to coolteam.co custom domain 🎉 🚀 .

So we want to support such scenarios for Ever Teams and I think it should be possible and relatively easily use Starter project provided above built by Vercel team.