Added yml upgrade instructions

README.md

@@ -333,6 +333,40 @@ And run
 rake db:migrate
 ```
 
+Update `config/blazer.yml` with
+
+```yml
+# see https://github.com/ankane/blazer for more info
+
+# data sources
+data_sources:
+  main:
+    url: <%%= ENV["BLAZER_DATABASE_URL"] %>
+
+    timeout: 15
+
+    smart_variables:
+      # zone_id: "SELECT id, name FROM zones ORDER BY name ASC"
+
+    linked_columns:
+      # user_id: "/admin/users/{value}"
+
+    smart_columns:
+      # user_id: "SELECT id, name FROM users WHERE id IN {value}"
+
+# create audits
+audit: true
+
+# change the time zone
+# time_zone: "Pacific Time (US & Canada)"
+
+# class name of the user model
+# user_class: User
+
+# method name for the user model
+# user_name: name
+```
+
 ## TODO
 
 - advanced permissions