Add structured errors to schema

db/migrate/20170703080355_create_structured_error_attributes.rb

@@ -0,0 +1,11 @@
+class CreateStructuredErrorAttributes < ActiveRecord::Migration
+  def change
+    create_table :structured_error_attributes do |t|
+      t.belongs_to :structured_error
+      t.references :error_template_attribute
+      t.string :value
+
+      t.timestamps null: false
+    end
+  end
+end