add: notice message skeletal code

db/migrate/20210909030759_create_message_templates.rb

@@ -0,0 +1,11 @@
+class CreateMessageTemplates < ActiveRecord::Migration[5.2]
+  def change
+    create_table :message_templates do |t|
+      t.string :type 
+      t.text :sys_notice
+      t.text :email
+
+      t.timestamps
+    end
+  end
+end