Docs updates (#6)

* Update django docs links to 4.0
* Update Django Q to Django Q2
* Use different theme to make difference more clear between the original and this forked one
* Added info notice about this fork
* Some small layout/typo fixes

docs/Dockerfile

@@ -0,0 +1,7 @@
+FROM sphinxdoc/sphinx
+
+RUN mkdir -p /docs
+WORKDIR /docs
+COPY . .
+RUN pip3 install -r requirements.txt
+RUN make html