Core DNS support

This feature leads directly on from the developer preview. The issues associated with it, should define what is needed to get to a more supportable and feature full Core DNS offering that could be used in none production environments for full evaluation.
Once this is completed, there should be very little in the way of breaking changes. Not that we wont make them if needed at this stage, but ideally all is well known and we are moving to a more complete feature set for Core DNS support.

The issue describes a broad Core DNS support effort but does not name files, tests, entry points, or individual acceptance criteria. Start by reviewing the related developer-preview issues and repository structure to identify the remaining work. Done means the Core DNS offering is sufficiently complete for non-production evaluation with breaking changes understood.

Written by the indexing model from the issue text.