Adjusted logging in a few classes.

Changed some System.err.println to logging statements.  Changed some
LOG.severe to LOG.info, since they are not fatal or even warn-level events.

My goal was to be able to suppress logging for command line use.  One of the 
System.err.println's I changed to logging is displaying a prompt.  I don't know
if this will affect any of the functionality.  My only test case has been for Kerberos
authtentication.  All unit tests pass with these changes.