Remove disclaimer around Django 2.x

Thanks to @jcass77, we now have 2.x support

README.rst

@@ -172,7 +172,3 @@ What's the Status of the Project?
 Stable.  I'm actively using it in a production environment now and have been
 for some time without issue.  This isn't a guarantee that it'll work for
 everyone in every case of course, but it's enough for me to use that word :-)
-
-Note however that currently, this module hasn't been adapted to work in Django
-2.0+, so if you're using that, feel free to issue a pull-request that allows it
-to work in both 1.11 and 2.0+ :-)