add nginx reverse proxy examples

examples/nginx-simple/docker-compose.yml

@@ -0,0 +1,18 @@
+version: "3"
+
+services:
+  plantuml-server:
+    image: plantuml/plantuml-server:jetty
+    container_name: plantuml-server
+    environment:
+      - TZ="Europe/Berlin"
+
+  nginx:
+    image: nginx:alpine
+    container_name: nginx
+    ports:
+      - "80:80"
+    environment:
+      - TZ="Europe/Berlin"
+    volumes:
+      - ./nginx.conf:/etc/nginx/nginx.conf:ro