Log Message:
Update trac AccountManagerPlugin to r4698.

r4698:
* Fix a bug where an error in the password store would fail to be reported
  correctly.
r4678:
* Fix HttpAuthStore so that it doesn't provide set_password or delete_user.
  This fixes it trying to create users.
r4639:
* Branching the 0.11 version in preaparation for a new release