Solution: remove implementation. Laurent Alebarde <l.alebarde@free.fr>,
the author, did not respond to requests to allow relicensing to MPL2,
so we have to remove his copyrighted work.
Make the API into an empty stub that returns -EOPNOTSUPP.
Solution: use ZMQ_LAST_ENDPOINT in most places. This alllows running
tests in paralle, and on over-booked shared machines where many of
the ports would be already in use.
Keep 3 tests with an hardcoded port, as there are some code paths that
require it (eg: connect before bind), but list those ports in
tests/testutil.hpp as macros so that they do not overlap and still
allow parallel runs.
These changes were inspired by a patch uploaded to Ubuntu by the
package maintainer, Steve Langasek <steve.langasek@ubuntu.com>.
Thank you Steve!