add layout for posts

Author: WSQS

_config.yml

@@ -15,6 +15,15 @@ collections:
     output: true
 
 defaults:
+  - scope:
+      path: ""
+      type: posts
+    values:
+      layout: single
+      read_time: true
+      comments: true
+      share: true
+      related: true
   - scope:
       path: ""
       type: "poem"