Attach event listener to the http(s) server.

Expose `upgrade` proxy handler on foxy `app` instance as `handleUpgrade`
Attach `upgrade` listener in CLI server creation.

Issue #2

cli.js

@@ -60,13 +60,18 @@ function handleCli (cli) {
  */
 function getServer (scheme, app) {
 
+    var server;
+
     if (scheme === "https") {
 
-        return https.createServer({
+        server = https.createServer({
             key:  fs.readFileSync(path.resolve(__dirname, "test/fixtures/certs/server.key")),
             cert: fs.readFileSync(path.resolve(__dirname, "test/fixtures/certs/server.cert"))
         }, app);
     }
 
-    return http.createServer(app);
+    server = http.createServer(app);
+    server.on("upgrade", app.handleUpgrade);
+
+    return server;
 }

lib/server.js

@@ -26,9 +26,9 @@ module.exports = function (config) {
      * Handle `upgrade` event to proxy WebSockets
      * https://github.com/nodejitsu/node-http-proxy#proxying-websockets
      */
-    app.on("upgrade", function (req, socket, head) {
+    app.handleUpgrade = function (req, socket, head) {
       proxy.ws(req, socket, head);
-    });
+    };
 
     /**
      * Proxy errors out to user errHandler