Make documentation production ready

I think we made massive progress towards full production readyness and think we need to adjust our documentation according to this, so it doesn't scare people so much as I would be when reading sth like:

i.e.:

https://docs.stackspin.net/en/v0.8/installation/install_cli.html:

Stackspin is still under heavy development and is not ready for production use! ... ... please do not use a server that functions as anything other than a testing ground.