Merged fixes from maintenance branch

core of the PR is here https://github.com/yast/yast-yast2/pull/120

Main difference is https://github.com/mchf/yast-yast2/commit/b8b377cc7695cb6c88113e9f59813e5b937eaf31
Comment on this: NetworkInterfaces#HasAliases is actually used. But it is only at one place in yast2-network for displaying second confirmation popup. So, it in my POV do not belong into yast2.rpm and I'm going to replace it in yast2-network.