That script is for a particular application that has nothing to do with Acrobat. Do you have access to Adobe Bridge, which comes with Adobe Creative Suite/Cloud? If so, it can do this with the Batch Rename feature. You can also do it using an Action withing Acrobat using a bit of JavaScript, but it wouldn't be a rename, it would be a save as to a new file, perhaps in a new folder, with the name you want. To save to a new file in the same directory, the script could be something like:
var sPath = path.replace(/\.pdf$/i, "-" + util.printd("yyyymmdd", new Date()) + ".pdf");
saveAs({cPath: sPath, bPromptToOverwrite: true});
This code can be executed in the JavaScript console to save the current document or included in an Action to save a collection of documents.
doc.saveAs documentation: http://livedocs.adobe.com/acrobat_sdk/9.1/Acrobat9_1_HTMLHelp/JS_API_A croJS.88.524.html