added Docker setup & moved database into instance folder

docker-compose.yml

@@ -0,0 +1,11 @@
+services:
+  eve_structure:
+    build: .
+    container_name: eve_structure
+    restart: always
+    ports:
+      - 5000:5000
+  
+    # store db and other stuff outside the container (skip init-db in Dockerfile)
+    volumes:
+      - ./instance:/app/instance