laravel/framework — pull request #3364 by girokon (2014-01-28 18:31:24+00:00)
Title: Add primary key for migrations

Without primary key, at the Windows this is queries is equivalent:
```SQL
SELECT* FROM migrations ORDER BY migration DESC
SELECT * FROM migrations ORDER BY migration ASC
```
hence the order wrong during migrations rollback

Tested on Windows 8 + MySQL 5.5