Call to setup_identity in onLogin function doesn't need to be
within login thread.  In fact, it can't be unless we rewrite
existing code, because we must run setup_identity() to populate
the cvlLoginHostComboBox before we read the value of the
cvlLoginHostComboBox which is done before the login thread is
started.

Fixed bug in last commit where "return True" was put in the
wrong place in the setup_identity() function.  The boolean
return value indicates that the identity was setup without
encountering any errors along the way.