Problem: missing use of C++11 = delete and = default

Solution: introduce macros ZMQ_DEFAULT and ZMQ_NON_COPYABLE_NOR_MOVABLE

src/router.hpp

@@ -123,8 +123,7 @@ class router_t : public routing_socket_base_t
     // will be terminated.
     bool _handover;
 
-    router_t (const router_t &);
-    const router_t &operator= (const router_t &);
+    ZMQ_NON_COPYABLE_NOR_MOVABLE (router_t)
 };
 }