feat(deployment) Allow overriding service host and ports with env variables (#930)

* Add proxy changes

* Add web changes

* Add microservices changes

* Add examples

* Add header comment to nginx config

* Use URLs instead of host and port

nginx/start.sh

@@ -0,0 +1,9 @@
+#! /bin/bash
+set -e
+
+export IMMICH_WEB_URL=${IMMICH_WEB_URL:-http://immich-web:3000}
+export IMMICH_SERVER_URL=${IMMICH_SERVER_URL:-http://immich-server:3001}
+
+envsubst '$IMMICH_WEB_URL $IMMICH_SERVER_URL' < /etc/nginx/nginx.conf.template > /etc/nginx/nginx.conf
+
+exec nginx -g 'daemon off;'