def destroy
      # Check to see if an external auth system should be used.
      auth_url = ::Incline::UserManager.end_external_authentication(request)
      if auth_url.blank?
        log_out if logged_in?
        redirect_to main_app.root_url
      else
        redirect_to auth_url
      end
    end
def destroy
      # Check to see if an external auth system should be used.
      auth_url = ::Incline::UserManager.end_external_authentication(request)
      if auth_url.blank?
        log_out if logged_in?
        redirect_to main_app.root_url
      else
        redirect_to auth_url
      end
    end
DELETE /incline/logout