Following modification improves boot time by not blocking services that do not
actually need network to be up:

/etc/systemd/system/network.service -> /usr/lib/systemd/system/wickedd.service

/etc/systemd/system/network-online.target.wants:
   wicked.service -> /usr/lib/systemd/system/wicked.service

/etc/systemd/system/network.target.wants:
   wickedd.service -> /usr/lib/systemd/system/wickedd.service

/etc/systemd/system/wickedd.service.wants:
   wicked.service -> /usr/lib/systemd/system/wicked.service


That way network.target only brings up wickedd which in turn triggers wicked
aka ifup in the background.