Rename NSEC4 to DNSNXT in abstract
Rename NSEC4 to DNSNEXT in middle.mkd
Remove to DNSNXT
Cleanups
Limit Iterations to one octet

This means changing DNSNXTPARAM also. Update all text that
mentions Iterations.
Kill all examples.

We now have RFC 7129 ! :)

This does not really add stuff. It should all be clear from the text.
remove entire appendix
Add changelog
changelog tweak
More tweaks
Fix merge conflict
beter abstract