[api] Emit `end` event when done proxying

lib/node-http-proxy.js

@@ -359,6 +359,9 @@ HttpProxy.prototype.proxyRequest = function (req, res, port, host, buffer) {
       if (!errState) {
         reverseProxy.removeListener('error', proxyError);
         res.end();
+        
+        // Emit the `end` event now that we have completed proxying
+        self.emit('end', req, res);
       }
     });
   });