### Bugs

Reported-by: Huangyu: I found dhcpd-pools didn't consider if the
   active lease's ends time is passed so it would still think the
   lease is active even if dhcpd daemon is stopped for a long time,
   the leases marked by "active" state in lease_file has expired in
   fact.

### Feature requests

o Assigned IPs count (Nelson)
o Subnet counting class (Henryk)
o When time stamps are part of lease situation evaluation (see
  bug 1) add a --now switch which will one can use to change when
  expiry happens.
o Add lease time histogram support.
