A default error.html template to go with the simple.errorResponse() view.
Patch by: Todd Larsen
Review by: to-be-reviewed
This is an optional add-on app, flatpages.
For full documentation, see either of these:
* The file docs/flatpages.txt in the Django distribution
* http://www.djangoproject.com/documentation/flatpages/ on the Web
Both have identical content.