The addition of the nc_hashmap to facilitate quick
retrieval of var and dim by name did not take into
account key collisions -- two or more names hashed
to the same value. If the keys matched, it assumed
that the names matched also.
This change fixes this incorrect assumption and
checks both the key (which is the hash of the name)
and if the keys match, it also checks that the names
match.
While there have been no instances of duplicate keys,
they are certain to occur and cause difficult to
debug issues. This fix eliminates that defect.
contain as little file-type specific info as possible. It
modifies especially libsrc so that all of the netcdf-3 data
that used to be in struct NC is now kept in a separate chunk
of data pointed to by the struct NC. This makes all of
current protocols consistent: netcdf-3, netcdf-4, and dap.
