Document service discovery

[lfrancke]

As a user of services deployed by this operator I'd like to know how to discover its connection details.

It's done when

• documentation is available on all the objects (e.g. ConfigMaps) created by this operator and the circumstances under which they are created and
• documentation on the contents of the created objects is available.

NOTE: This ticket is part of an epic and autocreated for all our operators. It might not apply to this operator in particular, in that case please comment and close
stackabletech/documentation#86