Improve documentation

[aojea]

There is a README but is outdated

It will be also nice to have some kind of static web as https://network-policy-api.sigs.k8s.io/api-overview/

[kenudeh]

Hello there! By static web, you mean a proper documentation site, right?

[kenudeh]

Just reviewed the /docs/testing folder, there doesn't seem to be any documentation at all for the project at the moment. Is this correct?