Fixed typo in RedirectingAction when no return-to data provided in form submission.
RedirectingAction::returnToArgs() has been renamed to returnToPrevious() to avoid conflict with Action::returnToArgs() which returns arguments to be passed to other actions as return-to arguments. All callers should now be updated.
More profile settings actions will now redirect through a login form if visited as a GET request, as would be expected from a bookmark, link sent in e-mail etc.
While deletion is in progress, the account is locked with the 'deleted' role, which disables all actions with rights control.
Todo:
* Pretty up the notice on the profile page about the pending delete. Show status?
* Possibly more thorough account disabling, such as disallowing all use for login and access.
* Improve error recovery; worst case is that an account gets left locked in 'deleted' state but the queue jobs have gotten dropped out. This would leave the username in use and any undeleted notices in place.
