Adds Dockerfile, docker-compose, and updates README.

docker-compose.yml

@@ -0,0 +1,10 @@
+services:
+  app:
+    build: .
+    restart: unless-stopped
+    env_file:
+      - .env
+    volumes:
+      - ./.env:/app/.env
+    ports:
+      - "3000:3000"