Establish a state ready for beta testing

[debuglevel]

On the last community call, Fred asked us to beta test Greenlight 3. But to be honest, this application does not feel like it is in a Beta state. If I noticed correctly, quite a few other admins from the german BBB matrix channel experienced similar issues and hesitate to test it.

• There is a scripts/deploy.sh which just... exits...?
• There is a master as well as a beta branch which both get some commits. No idea why they exist at all.
• README references a dev-v3 which does not even exist.
• IMHO this repository should not exist at all and is a mere indicator that https://github.com/bigbluebutton/greenlight/tree/v3 lacks essential parts.
• https://github.com/bigbluebutton/greenlight-run/blob/beta/data/greenlight/bin/start overrides the original start script without being documented. I guess this was done because the script in https://github.com/bigbluebutton/greenlight/tree/v3 is simply missing the stuff to load the schema. This should rather have been a pull request to https://github.com/bigbluebutton/greenlight/tree/v3 instead of overriding it.

Maybe it's possible to test it again internally at blindsight networks with somebody who never used Greenlight 3 before? This way some "works on my dev machine" issues could be circumvented and the README could be improved (although it's way better than what exists at https://github.com/bigbluebutton/greenlight/tree/v3)

bigbluebutton/greenlight#4165