rework README.md to contain a feature overview  (#412)
rework README.md to contain a feature overview  (#412)

* rework README.md to contain a feature overview together with (more technical) setup instructions.

* update compact

* added statictics information

* Feedback for PR 412

* Update README.md

updated with results of other review

* Update README.md

fix forum link

ioBroker/ioBroker.js-controller,ioBroker/ioBroker.js-controller,ioBroker/ioBroker.js-controller