code: function toRestifyHandler(handler) {
          if ((typeof handler === 'function') && (handler.length !== 3)) {
              //Wrap `virgilio-http` type handlers.
              handler = restifyHandler.bind(this, handler);
          }
          return handler;
      }
docs: Take a certain handler that might be a restify handler, or a virgilio-http handler (without next() and returning a promise). Return a restify handler.