マイグレーションに失敗

まだ追っかけてませんが、develop をクローンしてマイグレーションしようとすると以下のエラーが発生しました

```bashA
bin/rake db:migrate
== 20140628151137 AddUserIdToUpdateHistories: migrating =======================
-- change_table(:update_histories)
rake aborted!
StandardError: An error has occurred, this and all later migrations canceled:

SQLite3::SQLException: Cannot add a NOT NULL column with default value NULL: ALTER TABLE "update_histories" ADD "user_id" integer NOT NULL/private/tmp/lodge/db/migrate/20140628151137_add_user_id_to_update_histories.rb:4:in `block in change'
/private/tmp/lodge/db/migrate/20140628151137_add_user_id_to_update_histories.rb:3:in `change'
-e:1:in `<main>'
ActiveRecord::StatementInvalid: SQLite3::SQLException: Cannot add a NOT NULL column with default value NULL: ALTER TABLE "update_histories" ADD "user_id" integer NOT NULL
/private/tmp/lodge/db/migrate/20140628151137_add_user_id_to_update_histories.rb:4:in `block in change'
/private/tmp/lodge/db/migrate/20140628151137_add_user_id_to_update_histories.rb:3:in `change'
-e:1:in `<main>'
SQLite3::SQLException: Cannot add a NOT NULL column with default value NULL
/private/tmp/lodge/db/migrate/20140628151137_add_user_id_to_update_histories.rb:4:in `block in change'
/private/tmp/lodge/db/migrate/20140628151137_add_user_id_to_update_histories.rb:3:in `change'
-e:1:in `<main>'
Tasks: TOP => db:migrate
```