README teasers

[naorlivne]

Currently the README is just a go to readthedocs documents on all the repos, Thinking it could be better if it's some sort of a teaser showing Nebula potential in some way that aren't the full docs yet show people what Nebula is.

This is true for all of nebula-orchestrator repos & not just the docs repo.

I'm horrible at sells, anyone a bit more artsy\selly mind pitching in?

[naorlivne]

added a small one, but still think much more can be add