This fixes a number of issues:
- The hosts file refresher would load the records on boot, and then the
expiration code would immediately expire it. - Several situations where the RR would be extended instead of replaced,
in A, AAAA, and PTR situations. - PTRs were not being properly evacuated in a few situations.
- Named records were also not being evacuated if tickled right; this is
mostly related to situations where you have a hosts file and a named
record that were in conflict.