Use python logging in install / log cherrypy at right severity
    
    This replaces the print statements in the installer code with
    a python logger so we can log all output to the installer log
    and a subset of it to stdout in one step without duplication.
    
    The cherrypy.log.error() logs to the "error" log at a severity
    of logging.INFO by default. Set an appropriate log level for
    these as well.
    
    https://fedorahosted.org/ipsilon/ticket/35
    
    Signed-off-by: Rob Crittenden <rcritten@redhat.com>
    Reviewed-by: Simo Sorce <simo@redhat.com>