Patch fixed utils.config._get_database_engine for django 1.2.x

[Apkawa]

Hi.
I written path http://paste.pocoo.org/show/263575/

In django new config as DATABASES[key]['ENGINE']

[lamby]

This patch does not detect MySQL correctly - settings.DATABASES['default']['ENGINE'] is a dotted-notation string like "django.db.backends.mysql" so comparing with "mysql" is wrong.

Also, "default" should be replaced with DEFAULT_DB_ALIAS.

Also, you make an unrelated change to the end of the file.