tubearchivist/docs/Channels.md

All user documentation has moved to a more flexible, easier to extend and modify documentation platform accessible [here](https://docs.tubearchivist.com) and built from [here](https://github.com/tubearchivist/docs). Don't make any more changes here, keeping this around for some time to keep old links alive.

Equivalent Channels page is: [here](https://docs.tubearchivist.com/channels/).