Switch to rancher's local storage provisioner
We have developed our own local storage provisioner, because there didn't seem to be one available back when we started the project, at least not in a usable form.
By now, rancher's local-path-provisioner seems to be in a good shape. It is mostly identical to ours in functionality. We should test if it works in our setup and if so, switch to that. This will reduce our maintenance load.
This will automatically solve #561 (closed) , as rancher's provisioner already uses the naming scheme for local directories that we wanted to implement for local-storage#12 .