Update on briar, Span project, JOKER protocol etc.

[Neudrino]

Hello @moarpepes,

sorry for the mess, this is my first use of github! I wanted to have different pull requests for different edits, however, it all got in this one. Maybe I would have to created more branches and merged them back (but I only edited my forked master)?

I digged through the internet on that topic for a while now. Originally in search of a mobile app to use when abroad with friends or family. Now I wanted to summarize my readings (for me) and found your repo. Thought I could contribute... ?

[moarpepes]

Thanks for taking the time to add more mesh projects. However, you seem to be missing licensing information. Please consider adding it and/or removing closed-source projects like GoTenna.

You might also consider squashing some of the commits.