Look for the zmq C level interface instead of the C++ interface.

Starting with version 3.0 zmq doesn't package the C++ interface anymore,
instead it offers it as a secondary download, so instead look for the C
interface. We never needed the C++ interface anyway as we have a fork
of the C++ interface inside remus.

Change-Id: I467d368f950fb18db94f2d641caa9a3a04ed4d6f
No need to force msvc builds to use static let the user decide that info.

Change-Id: If66e9c21f031308c2bd8d7ba56e113599b3e8849
Merge branch 'boost_windows_static'

Change-Id: Ifbbe9239d1e09e5fd5b0689db5536e640f6f8c86