Discuss (review 2017-10-15)

[matje]

Discussed with @fanf2 on the topic of additional section processing:

• Additional section processing for resolvers may be slightly different than the processing that happens on the authoritative.
• Target address records likely not needed in additional section: When an authoritative server receiving an address query just the ANAME should go in the additional section: The (already expanded) sibling address records need to go in the answer section.
• The terminology with respect to target records can be improved: What is a target record, does it include the owner name or is it just the RDATA? Perhaps we need split up the definitions into target record and target RDATA.
• A use case would be useful

[fanf2]

I've merged some of this PR, and moved some of the commits to a "discuss" branch until I can turn them into issues.

There are some discussions inside the draft which also need to be moved to issues.