refactor field validation, hex_digest setting and bring in assertRaisesMessage
remove line that I accidentally left before commit
Merge branch 'master' of github.com:ConsumerAffairs/django-urlographer

Conflicts:
	urlographer/models.py
	urlographer/tests.py
fix test that broke with model validation changes
make hexdigest readonly and site a choice field when in admin
Merge pull request #3 from jsatt/master

Improve model validation and admin interface