fix manage.py calls in postinst

postinst

@@ -2,20 +2,26 @@
 
 set -e
 
+MANAGE="python /usr/lib/passerelle/manage.py --config=/usr/lib/passerelle/debian_config.py"
+
 case "$1" in
   configure)
+
+    # make sure the administrative user exists
     if ! getent passwd passerelle >/dev/null; then
       adduser --disabled-password  --quiet --system \
         --no-create-home --home /var/lib/passerelle \
         --gecos "Passerelle software user" --group passerelle
-      chown passerelle:passerelle /var/log/passerelle
-      chown passerelle:passerelle /var/lib/passerelle
-      chown passerelle:passerelle /var/lib/passerelle/media
     fi
-    /etc/init.d/passerelle manage collectstatic --noinput --link
+    # ensure dirs ownership
+    chown passerelle:passerelle /var/log/passerelle
+    chown passerelle:passerelle /var/lib/passerelle
+    chown passerelle:passerelle /var/lib/passerelle/media
+    # populate /var/lib/passerelle/collected-static
+    $MANAGE collectstatic --noinput --link
   ;;
   reconfigure)
-    /etc/init.d/passerelle manage collectstatic --noinput --link
+    $MANAGE collectstatic --noinput --link
   ;;
 
   abort-upgrade|abort-remove|abort-deconfigure)