Update ContentTypes and Permissions

```
When app names change or apps are deleted, the Permissions tables in Admin
get out of whack. This script fixes the problem:

http://www.djangosnippets.org/snippets/696/

I've needed this on every Django project I've worked on so far. Would be
great to have it available as a command extension.


```

Original issue reported on code.google.com by `shacker....@gmail.com` on 17 Sep 2009 at 6:48
