Add an array of arguments to isReadOnly() method of actions, to let
them change their results depending on what actions are called.
Primarily used by the 'api' action. Ideally in the future that will be
multiple actions. But this might still be useful.
I've seen a request or two pop up for this on the Laconica group on
Identica, and I'd personally like there to be a link to the search
page from my own groups listing, as I often find myself looking for
one and end up at my browser's address bar.
