netcdf-c

Merged in pnetcdf fixes from Greg Sjardema, to make set_fill_mode work
with parallel-netcdf, to fully implement parallel-netcdf support for
other functions, and to prevent a hang in hdf5 from an eary return in
an nc4_put_vara() call.  Also fixed an nccopy bug when
nc_inq_var_deflate() returns defalate_level of 0, but says the variable
is deflated.