Missed another direct reference to user.id.

Please merge and release :)
The tests now use a user with a custom id field.
Fixed the get_anonymous_user() method which used explicit id instead of pk.
Reordered wording so it makes more sense
Merge pull request #236 from vlal/bugfix/fix-documentation-error

Reordered wording so it makes more sense
Merge branch 'master' into devel
Merge pull request #235 from thedrow/patch-1

Missed another direct reference to user.id.
Merge branch 'master' into devel
Merge branch 'devel' of github.com:lukaszb/django-guardian into devel