Add note for Mountain Lion Safari bug fix in Readme

Author: danrodney

README.md

@@ -23,6 +23,7 @@ You can change the duration of your animations, add a delay or change the number
 ```
 
 *Note: be sure to replace "vendor" in the CSS with the applicable vendor prefixes (webkit, moz, ms, o)*
+*Note: Safari in Mountion Lion (OS 10.8) has a display glitch with the Flippers. They may not appear at all until the animation is completed, or the page may have other artifacting. One fix is to add overflow: hidden to the parent div.*
 
 ##License
 Animate.css is licensed under the ☺ license. (http://licence.visualidiot.com/)