In shAutoloader.js: Only load the script which is not loaded

Hello,
I found that if I write the same brush tags in my post, the autoloader will load several duplicate scripts.
http://i.minus.com/iZnQUf2grvljw.png

So I add a check in the code.
Now only with one request.
http://i.minus.com/iuYtg7MbOlxyR.png