Probably fixed #3
A `content_type` field on the SearchIndex clobbers
the `content_type` method on the SearchResult
instance because of the underlying __dict__ being
set directly.

Thanks to Ben Hastings for reporting the issue.
Fixed #4
GitHub broke my README, so no more symlink, now
`docs/about` does an include, as seems to be how
cookiecutter packages are doing it.
bugfix: if there are no available models, raise the 404 correctly, instead of ending up in an infinite loop.
Also subclassed all the 404s in use, should the need ever arise to determine what type of 404 is being encountered.
bugfix: template syntax error introduced in 46fa79c
bugfix: NoReverseMatch introduced in 46fa79c
replace force_unicode with force_text where possible.
Django 1.6 drops update_wrapper from being in the functional compat library.
doesn’t need to be unicode, and is better compatible with py3.
Looks like this is required on newer versions of Django, which is ironic, as I pointed out that it didn’t work years ago.
if multiple connections are defined, it needs to not throw up an exception under py3
add debug logging