advanced cert creation form view

[bennomadic]

little link that shows the advanced form.
(ajax-y?)

To be added:

• Show key bits selector if it was hidden.
• Custom expiration overrides: days, even hours.
  (very useful for temporary cert installation. make user aware of that possibility:
  i.e., you are in a public computer: create a temp cert, use it, and revoke it.
  other possibility: mark a cert as one-shot, and have it automatically revoked after session
  expiration :)
• Custom common name?