laravel/framework — pull request #3363 by girokon (2014-01-28 18:06:20+00:00)
Title: Fix migrations rallback

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 8.1 + MySQL 5.5 && MySQL 5.6