encapsulated link; the vinterfaces were not getting updated properly.

I am not happy with the change mentioned above, but I needed it to
make vlan tag pre-reservations work; the encapsulation vlan has a
generated name, and that is hard to match up with the tag that is
reserved before the experiment is created, as from the protogeni
interface when stitching. I plan to come back and redo this after the
GEC.