version 0.5.26

• rpm: drop useless ghost dirs in spec (bnc#873857)
• client: do not try to fire nanny in ifdown, it is not hired yet
  We do not install nanny policies by default in ifup, so it is
  not needed to try to delete them in ifdown. There is currently
  no nanny started in inst-sys and the attempt is causing ifdown
  to run into timeouts (bnc#876848,bnc#879127).
• client: wait for optional leases, just don't fail
  When waiting for a group-optional lease pair (dhcp4 or dhcp6)
  and one arrives, wait for the second one until timeout and
  recheck the results then (bnc#876848,bnc#879127).
• dhcp6: fix reset and allocate message buffer in build to use
  clean buffer in release messages sometimes having crap behind.