1. Synch the opendap grammar with that of oc
   so they are consistent.
2. (re: esupport ZQI-388461)
   Rich Signell noted that opendap crashed when
   a Grid array had a duplicate dimension. This
   actually illegal according to the DAP2 spec.
   So, instead, when this occurs, we just pass thru
   the variables as top-level insterad of attempting
   to convert them to a grid.