Add support to report how long a entry has been in error.
add the ability to specify a database to record this information. use a key of or <zone,server,type> or < zone,server,address> depending upon the error type. record the fail timestamp on error, do not update if it already exists. clear the above keys on success where success is:
- ns lookup succeeded for
- address lookup succeeded for <zone,server,type>
- tests succeeded for zone,server,address>