disable about and settings by default (#1868)

* disable about and settings by default

* support docker variables

* remove comments

docker/docker-entrypoint.d/30-sed-on-app-extensions.sh

@@ -0,0 +1,15 @@
+#!/bin/sh
+
+set -e
+
+echo Running sed on "${NGINX_ENVSUBST_OUTPUT_DIR}/assets/app.extensions.json"
+
+# modifies the "$ignoreReferenceList" property using a comma-delimited string
+if [ -n "${APP_EXTENSIONS_IGNORE_REFS}" ]; then
+echo "replace APP_EXTENSIONS_IGNORE_REFS"
+
+  replace="\/"
+  encoded=${APP_EXTENSIONS_IGNORE_REFS//\//$replace}
+  sed -e "s/\"$ignoreReferenceList\": \".*\"/\"$ignoreReferenceList\": \[${encoded}\]/g" \
+    -i "${NGINX_ENVSUBST_OUTPUT_DIR}/app.extensions.json"
+fi