* To do:
          + negative caching
          + progress bar (with ETA)
          + resolve the last few unresolved IPs. I'm looking into a whois
            lookup or a "closest hop" approach
          + arrange benchmarks into a comprehensive table
          + test with Perl 5.6.0 (waiting for woody packages :P)
     * Done:
          + direct STDIN input (0.3)
          + add ability to edit databases create with "--database"
            (0.5.1)
          + clean up "dangling" A/B/C class sockets during run (0.6.0)
          + expire database entries (0.6.0)
          + further optimizations (getresolved()) (0.6.0)