Modifying a PurplePluginAction label

[Matí­as Alejandro Torres]

Etan Reisner escribió:
> What are you trying to do with your menu items that you need them to
> change frequently?
>   
Now, the menu item says "Toggle status change" no matter the current 
status of the plugin. It's kind of anoying because you never now wether 
you're activating or deactivating the plugin. I want that the label of 
the menu item changes dependgin its status, "Activate status change" 
when it is deactivated and "Deactivate status change" when it is active. 
It's simple task but I just don't know how to change the label!

Matias