simplifying css selector for hiding buttons at the bottom of the addon manager.
simplifying css selector for hiding buttons at the bottom of the addon manager.

HasClass0/greasemonkey,Ventero/greasemonkey,Martii/greasemonkey,Ventero/greasemonkey,the8472/greasemonkey,HasClass0/greasemonkey,Martii/greasemonkey,the8472/greasemonkey