+zmq.3.2-0

This is a maintained version of `ocaml-zmq`, which is pointing at
an unstable tarball.  The other will be deprecated in favour of
this package in a month if not otherwise updated.

See <http://lists.ocaml.org/pipermail/opam-devel/2014-February/000420.html>
for the discussion on this topic.
zmq: fix depext
Merge pull request #1688 from mirage/master

+zmq.3.2-0