Proliferation of dev docs on search engines confuses newbies

[Dan Loewenherz]

I brought this issue up earlier today at DjangoCon, but the basic issue can be summarized hence:

1. User searches to find info on a specific feature, gets directed to dev documentation.
2. Said feature (on the development version) is backwards incompatible with previous versions of Django.
3. User does not know better, assumes Django has a bug.
4. Invalid bug is filed in trac.

Hopefully, removing the dev documentation pages from search engines will help solve
this issue, since those who want to read the dev docs can just click through to
them by using the version navigation at the bottom of the docs pages.

I think there is a small subset of actual Django users who run their applications
on trunk. I don't have data to back that up but I can't imagine it's a lot.

I talked with Alex earlier today about how to deal with this issue--he also suggested
redirecting users from dev -> 1.4 (or whatever the latest version is). I initially
thought it was a good idea, but I thought about it and realized you would have to at
least add some sort of referrer check. I then thought whether it would be ok to do
something like

    def conditional_documentation_redirect(request):
        if not request.META['REFERER'].startswith("http://docs.djangoproject.com"):
            return HttpResponseRedirect #... and so on

This felt wrong to me because if that sort of check were in place, users would
no longer be able to permalink to dev docs.

PR @ ​https://github.com/django/djangoproject.com/pull/43