doc: The REST API can now be used with Django < 1.8

The release notes stated that the REST API was only compatible with
Django 1.8. However, with the merge of commit '646366cc', this is no
longer the case.

We would rather people didn't use these older versions of Django, but
let's not lie.

Signed-off-by: Stephen Finucane <stephen@that.guru>

Author: stephenfin

releasenotes/notes/initial-reno-68c116ae9c5259a3.yaml

@@ -24,11 +24,8 @@ features:
     - Series
     - Cover letters
 
-    For information on the usage of the API, refer to the documentation.
-
-    Note that this feature depends on a combination of Django REST framework
-    and Django Filter, which in turn require Django 1.8+. As a result, Django
-    1.8 or greater must be used when the REST API is enabled.
+    For information on the usage of the API, refer to the `documentation
+    <https://patchwork.readthedocs.io/en/latest/api/rest/>`__.
   - |
     Cover letters are now supported.
 
@@ -71,19 +68,20 @@ features:
     supported.
   - |
     `Docker <https://www.docker.com/what-docker#/developers>`_ support is now
-    integrated for development usage. To use this, refer to the documentation.
+    integrated for development usage. To use this, refer to the `documentation
+    <https://patchwork.readthedocs.io/en/latest/development/installation/>`__.
 upgrade:
   - |
     The REST API is enabled by default.
 
-    The REST API is enabled by default when using Django 1.8. It is possible to
-    disable this API, though this functionality may be removed in a future
-    release. Should you wish to disable this feature, configure the
-    `ENABLE_REST_API` setting to `False`.
+    The REST API is enabled by default. It is possible to disable this API,
+    though this functionality may be removed in a future release. Should you
+    wish to disable this feature, configure the ``ENABLE_REST_API`` setting to
+    ``False``.
   - |
-    The `parsemail.py` and `parsearchive.py` scripts have been replaced by the
-    `parsemail` and `parsearchive` management commands. These can be called
-    like any other management commands. For example::
+    The ``parsemail.py`` and ``parsearchive.py`` scripts have been replaced by
+    the ``parsemail`` and ``parsearchive`` management commands. These can be
+    called like any other management commands. For example::
 
       $ ./manage.py parsemail [args...]
 fixes: