Visualize zone parent/child relationships

[peteeckel]

Is your feature request related to a problem? Please describe.
Since NetBox DNS has all information required to visualize parent/child zone relationships in the Zone detail view it would make sense to provide this additional information to the users.

Describe the solution you'd like

• Add a "Child Zones" tab to the zone detail view. That tab contains all direct child zones, i.e. the zones that have exactly one additional label on the left side of their name, and are in the same view as the zone itself. Indirect children (zones that have more than one label on the left side of their name) and zones in a different view will not be displayed.
• Add a "Parent Zone" row to the zone detail view if the zone with the name that results from removing the leftmost label from the zone's name and the same view exists in NetBox DNS.

This can be implemented on model and view level, without any changes to the database.