The above mod just lets you do it in one click and stays on current page instead of three clicks (->Preferences click Update) and changing page to Preferences, then at least one click to return to the page you were on.

If you're making changes to css it saves a few clicks and time everytime you update

Joe

Whilst looking for something else I discovered there were already a few functions in FA that clear the cache

So added to renderer.php

If you want an icon:-

File: \themes\default\renderer.php
87:                 $dimg = "<img src='$path_to_root/themes/".user_theme()."/images/remove.png' style='width:14px;height:14px;border:0;vertical-align:middle;' alt='"._('Delete Cache')."'>&nbsp;&nbsp;";

Then add:-

File: \themes\default\renderer.php
097:                 function delete_company_cache(){
098:                     flush_dir(company_path().'/js_cache');
099:                 }
100:                 echo "<a class='shortcut' href='?delete_company_cache=true'>$dimg" . _("Delete Cache") . "</a>&nbsp;&nbsp;&nbsp;\n";
101:                 
102:                 if(isset($_GET['delete_company_cache'])){
103:                     delete_company_cache();
104:                 }

It does not disable cache, just clears cache just for the company you are logged on to when you want from any page

Refer:
http://bertanguven.com/disable-caching-of-assets-in-apache
https://stackoverflow.com/questions/11532636/how-to-prevent-http-file-caching-in-apache-httpd-mamp
https://gist.github.com/JamieMason/3245483