Add PREPARATION_DONE flag to app.sh

deployment/docker/app.sh

@@ -45,6 +45,8 @@ if [ ! -e "$HOME/$ADMIN_CREATED" -a -n "$DJANGO_CREATE_ADMIN_PASSWORD" ]; then
     touch $HOME/$ADMIN_CREATED
 fi
 
+touch $HOME/PREPARATION_DONE
+
 if [ "$1" == "webworker" -o "$STARTMODE" == "webworker" ]; then
     # start gunicorn (might be called indirectly via supervisor when started with 'all')
     gunicorn_params=()