1. The code to parse a constraint
was losing the initial double quote
for a quoted string.
2. The code in ncuri.c was not properly
   handling occurrences of e.g. %xx



git-svn-id: https://sub.unidata.ucar.edu/netcdf/trunk@3239 2e3060e4-1ed8-cf1f-9cc2-9586e844a556