conf/completion: Autocomplete remote parcel names
conf/completion: Autocomplete remote parcel names

- Autocomplete names of parcels on the server for checkout, hoard, resume,
ls, and clean.  We cache the parsed output of "isr ls" so that we don't have
to do a server operation for every completion.  Caches are considered stale
after 30 minutes and removed.

cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr,cmusatyalab/openisr