get libs from distant servers to local (& avoid unnecessary requests to servers that logs user's connections)
ex:
https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js
becomes
getlib.php?url=https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js
if you want to update local file if the distant one changes, just add "update"
getlib.php?update&url=https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js
author: warriordudimanche.net