WIP: Removes Discourse iframe + sync

[viktorsmari]

Work in Progress

See #505

Todo:

• [ ] Maybe we want to keep some connectivity, so maybe not remove all connections?
• [x] Remove discourse iframes from machines/labs/orgs
• [ ] Check Analytics if https://fablabs.io/discuss is being used. Remove it?
• [ ] Remove the discourse Gems
• [ ] Remove the rest of discourse files
• [ ] Remove the routes
• [ ] Remove variables not needed anymore