re-add account migration

db/migrate/20170331024747_create_accounts.rb

@@ -0,0 +1,10 @@
+class CreateAccounts < ActiveRecord::Migration[5.1]
+  def change
+    create_table :accounts do |t|
+      t.string :title
+      t.string :account_type
+
+      t.timestamps
+    end
+  end
+end