Uninstall scripts, on closing Add Ons Manager.
Uninstall scripts, on closing Add Ons Manager.

Closes #1225

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