deploy: Error out if we see usr/etc
deploy: Error out if we see usr/etc

This version of the code doesn't know what to do with new-model trees,
so just abort if we see that.  We'll likely never care about upgrades
from 1.0 to 2.0.

GNOME/ostree,leandrosansilva/ostree,leandrosansilva/ostree,gatispaeglis/ostree,gatispaeglis/ostree,resin-io/ostree,GNOME/ostree,resin-io/ostree,sujitfulse/ostree,leandrosansilva/ostree,GNOME/ostree,sujitfulse/ostree,GNOME/ostree,GNOME/ostree,resin-io/ostree,sujitfulse/ostree,resin-io/ostree,gatispaeglis/ostree,gatispaeglis/ostree,sujitfulse/ostree,leandrosansilva/ostree,leandrosansilva/ostree,resin-io/ostree,sujitfulse/ostree,gatispaeglis/ostree,gatispaeglis/ostree