Thanks @sihui.
Problem is fixed now, looks like apt-get update/upgrade for whatever reason failed when I did it 2 days ago. I did it again after which all my bindings were gone 
After re-installing them (including ZWave), deleting the things and adding them again I was able to use the blinds channel.
I just found that the problem that bindings are gone is known: https://community.openhab.org/t/oh2-upgrade-of-today/15560
Thanks for the help
