Created new subclass Head to represent head tags.
Created new subclass Head to represent head tags.

UWPCE-PythonCert/IntroPython2016,weidnem/IntroPython2016,weidnem/IntroPython2016,weidnem/IntroPython2016,UWPCE-PythonCert/IntroPython2016,UWPCE-PythonCert/IntroPython2016