Add Budget::Investment::Status migration

db/migrate/20180321180149_add_status_to_milestones.rb

@@ -0,0 +1,8 @@
+class AddStatusToMilestones < ActiveRecord::Migration
+  disable_ddl_transaction!
+
+  def change
+    add_column :budget_investment_milestones, :status_id, :integer
+    add_index :budget_investment_milestones, :status_id, algorithm: :concurrently
+  end
+end