#452 Crao theme logged in vs. authenticated

[Philip J. Hollenback]

When a user logs on (is authenticated) in the Crao
theme, the topbar says 'you are signed in as XXXX'.

After the login times out, the topbar still says, "you
are signed in as XXXX'. However, what it really means
is you are now logged in but not authenticated, and if
the wiki is locked, you can't edit it until you log on
again.

That's confusing to users. The default theme handles
this by changing the message to "you are signed in but
not authenticated as XXXX'. This should be consistent
across all themes.