Really fix package initial installation when PID1 is systemd (Closes: #747863)

debian/nut-client.prerm

@@ -0,0 +1,13 @@
+#!/bin/sh
+set -e
+
+handle_start_failure () {
+# The MODE defined in /etc/nut/nut.conf shouldn't affect the exit code when the
+# daemon is stopped. If it fails to stop, the maintainer script should fail
+# too.
+  return 1
+}
+
+#DEBHELPER#
+
+exit 0