Fix for OpenID-only private sites: we were removing the 'login' and 'register' action...

Fix for OpenID-only private sites: we were removing the 'login' and 'register' actions from the routing system entirely, which meant that login links & redirects from unauthenticated views on private sites (as well as various re-auth situations even on non-private sites) would break and send to the main page instead.

Changed it to leave the 'login' and 'register' actions in the system; we're already taking them over and redirecting them to the OpenID login page, so they won't be reached by accident; but now those redirects can be reached on purpose. ;)
Better long-term fix may be to allow some aliasing, so we can have common_local_url('login') actually send us straight to the OpenID login page instead of having to go through an intermediate redirect, but this'll do.