Add blog deployment

roles/blog/templates/docker-stack.yml.j2

@@ -0,0 +1,20 @@
+version: '3.4'
+
+services:
+  app:
+    image: "{{ stack_image }}:{{ blog_version }}"
+    healthcheck:
+      test: ["CMD", "wget", "--spider", "-q", "localhost"]
+      interval: 1m
+      timeout: 10s
+      retries: 3
+      start_period: 1m
+    entrypoint: sh -c "/docker-entrypoint.sh nginx -g 'daemon off;'"
+    networks:
+      - "{{ docker_swarm_public_network_name }}"
+
+networks:
+  "{{ docker_swarm_public_network_name }}":
+    external: true
+
+