Update browser-sync.js

bug fix, custom middleware not working on proxy mode.

Author: yanwsh

lib/browser-sync.js

@@ -424,7 +424,7 @@ BrowserSync.prototype.addMiddleware = function (route, handle, opts) {
     }
 
     bs.options = bs.options.update("middleware", function (mw) {
-        return mw.concat(entry);
+        return (bs.options.get("mode") === "proxy")? mw.insert(mw.size-1, entry) : mw.concat(entry);
     });
 
     bs.resetMiddlewareStack();