mod_updateversion has one simple task, it refreshes the Media Version so your visitors will see updates you have to made to css and js files. The module runs once and then unpublishes itself.
Install the module and set position as debug and show on all pages. When you want to refresh the media version publish the module, then go to your site frontend and visit any page. Sometimes you have to reload the page a second time to pick up the new media version.
mod_updateversionv2.0.1