re: esupport 31942
* Add a new set of remote tests based on using the opendap hyrax server
* Re-enable --enable-dap-remote-tests as default on
* Make it possible to query the DMR separate from the DAP
so that it is possible to delay reading data until it is actually
requested. This make things like ncdump -h much more efficient.
* Fix handling of <Map>s in DMRs.
* Fix some memory leaks