add docs: batch jobs quickstart

[jfunez]

Is your feature request related to a problem? Please describe. We have batch jobs implemented but poorly documented. Since we have also mkdoc up and running, we must improve the docs

Describe the solution you'd like a quick-start guide with one complete example should be enough

Describe alternatives you've considered As an alternative, an use-case oriented approach should be good too.

Additional context n/a