Test glib networking
Test against glib-networking during configure phase.
Why do we need both?
- curl doesn't support https on windows because of a bug, glib-networking does but does not support http on windows
- on linux both work for both
- on mac, glib-networking (gio in fact) doesn't work
- moving queries from http to https slows them too much, but:
An HTTPS endpoint is also available at https://cdsweb.u-strasbg.fr/cgi-bin/nph-sesame[/-opt][/~SNVA]?object_name[&other_object_name]...