[fix] use the main export for EE3

Author: jcrugzz

lib/http-proxy/index.js

@@ -1,7 +1,7 @@
 var httpProxy = exports,
     extend    = require('util')._extend,
     parse_url = require('url').parse,
-    EE3       = require('eventemitter3').EventEmitter,
+    EE3       = require('eventemitter3'),
     http      = require('http'),
     https     = require('https'),
     web       = require('./passes/web-incoming'),