Merge pull request #326 from kmroz/fix-309

iflist: fix link type detection for tap devices
Merge pull request #327 from pwieczorkiewicz/match_fix

ifup: fix <match> generation to reflect <child> relationship correctly
Merge pull request #328 from mtomaschewski/dhcp4-no-netmask

dhcp4: use address class netmask if missed (bnc#887586)
dhcp4: use a helper for netmask/cidr conversions
dhcp4: handle prefix-len 0 in cidr to netmask
Merge branch 'master' into testing