- check if a user is suspended, and if so return some information about
    it
  - change a users password to the given password

Removed the implementation of get_user_info, which is no longer needed now
that by default information is sourced from the database by the
authentication stuff.

those things at the appropriate moments. Suspended/expired users can't log
in.

Made sure that password change checking is done in the correct places when
a user has logged in.

Fixed some subtle authentication bugs, such as when a session times out
immediately after logging in, where before the behaviour was undefined.

for checking whether a user's account has been suspended.

PHP side.

very intuitive behaviour.

is public. Check for the password having being changed just after the
login_submit function has determined that the user is logged in.

and implementing the change form.

usernames/passwords are valid. Made the encrypt_password method public, so
it can be used when changing the password for a user. Use 'self' instead of
a broken class name.

be removed.

  * Removed three methods that are unused
  * Changed log_dbg calls to log_debug, which is what the function is now
    called
  * Removed language section reference that only adds bloat now there is a
    default
  * Removed a couple of done TODOs
  * Added a function that allows each authentication method to validate
    their own configuration form.

slurping cancel requests from other forms.

and fixed up references to Auth_* classes.

stuff no longer needed.

follow, but also to support the form validation a lot better.

an authentication configuration form for each plugin.
Use redirect() instead of header() and exit.
Use helper function to call a static method when we have the class name in
a variable.
Some better commenting for the login related form functions.