Please update ifupdown in testing to version 0.6.8

[Petter Reinholdtsen <pere@hungry.com>]

Please allow the new ifupdown version 0.6.8 in unstable to propagate
into testing.  It fixes a longstanding deadlock problem, as well as
make the dhcp lease information survive reboots.  It has stayed in
unstable for 33 days without any problems being reported.

This is the changelog entry after the version currently in testing:

 ifupdown (0.6.8) unstable; urgency=low

   * Add myself as co-maintainer with approval from Anthony Towns.
   * Change path of dhclient.leases to make sure the dhcp state survive
     reboots. (Closes: #311777)
   * Change leasehours option value to match the option name.
   * Async ifup/ifdown modication based on patch from Scott James
     Remnant and Ubuntu.  (Closes: #347580)
     - Rewrite the way that ifup and ifdown read and write the state
       file.  Instead of storing it in memory and holding a lock on it
       (preventing concurrent processes from actually being concurrent)
       use atomic read and write functions that only hold the lock for
       very short periods.
     - Write to the state file when we start bringing up or tearing
       down the interface, so we don't ever try to do the same
       operation at the same time.
     - Update the state file once the operation is complete to ensure
       we record the actual status of it.
   * Acknowledge NMUs. (Closes: #311011, #311443, #353154, #339834, #311928,
     #336931, #338849, #362093, #330230, #386794, #384866, #312988, #266021,
     #384438, #387155, #387453, #387677)

Friendly,
-- 
Petter Reinholdtsen