Updated libzmq to match RFC 23, 24, 25, 26

* Command names changed from null terminated to length-specified
* Command frames use the correct flag (bit 2)
* test_stream acts as test case for command frames
* Some code cleanups

tests/test_security_curve.cpp

@@ -17,12 +17,12 @@
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#include "platform.hpp"
 #include <string.h>
 #include <stdlib.h>
 #include "testutil.hpp"
 #include "../include/zmq_utils.h"
 #include "../src/z85_codec.hpp"
+#include "../src/platform.hpp"
 
 //  Test keys from the zmq_curve man page
 static char client_public [] = "Yne@$w-vo<fVvi]a<NY6T1ed:M$fCG*[IaLV{hID";