[test/windmill] Gracefully skip windmill test if windmill can't be imported. If windmill import fails the windmill module is set to None and a dummy CubicWebWindmillUseCase test class is create. This class contains a test that skip itself with a proper warning message.

#! /bin/sh -e
 
case "$1" in
    purge)
	rm -rf /etc/cubicweb.d/
	rm -rf /var/log/cubicweb/
	rm -rf /var/lib/cubicweb/
    ;;
esac
 
#DEBHELPER#
 
exit 0