Switch to django-appconf.

This makes it much easier to view the list of settings,
and avoids repeated calls to ``getattr(settings, 'FOO', default)``
that lead to inconsistent default values.
Add 'author' field to snippets.
Update .gitignore
Fix 'about' page.

The example should have 4 letters, as stated above.
Set URL / domain from settings.
about: Add missing slash.
Add anti-spam badword triggers.
Allowing uploading a snippet or a binary file

So images can be uploaded and displayed.

Conflicts:
	dpaste/forms.py
	dpaste/models.py
	dpaste/urls/dpaste.py
	dpaste/views.py
Remove server/ config.
Cleanup settings.
Switch to django.utils.timezone.