Remove poller on hubzilla uninstall

src/freedombone-app-hubzilla

     sed -i '/hubzilla/d' $COMPLETION_FILE
     sed -i '/hubzilla/d' /home/$MY_USERNAME/README
     sed -i '/Hubzilla/d' /home/$MY_USERNAME/README
+    sed -i '/poller.php/d' /etc/crontab
 
     function_check remove_ddns_domain
     remove_ddns_domain $HUBZILLA_DOMAIN_NAME