Enable TLS by default and add UI for client/daemon auth

Turns on TLS by default and uses public keys to authenticate access.

- This PR still may require further testing and input on the user experience.
- FSNotify support has not been added to detect changes to authorized_keys
- Implementation of proposal from #7667

@bfirsh please review and comment on whether this is missing anything needed
I share your concerns about making a big change, but I think the problem is that this change will make an already confusing experience _even more_ confusing. I don't think there'll be much opposition to cleaning up the TLS options. :) /cc @crosbymichael