[c-c create] make post-create step optional (closes #2712041) In this context the "post-create" step refers to the database's creation and initialization. We want to be able to create a new instance but skip the database creation (`db-create` and `db-init` commands) in automatic setup.

#! /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