docs: Improve installation instructions

- Move allauth integrations details to installation.rst, instead of
  spearding out those instructions over two files.
- Mention configuring INVITATIONS_ADAPTER, as mentioned in
  docs/configuration.rst
- Improve formatting and add links.
- Mention that newer versions of Django and Python are supported.

docs/installation.rst

@@ -4,20 +4,20 @@ Installation
 Requirements
 ------------
 
-Python 3.7 to 3.10 supported.
+Python 3.8 to 3.12 supported.
 
-Django 3.2 to 4.0 supported.
+Django 3.2 to 5.0 supported.
 
 Installation
 ------------
 
-1. Install with **pip**:
+1. Install with `pip <https://pip.pypa.io/>`_:
 
    .. code-block:: sh
 
        python -m pip install django-invitations
 
-2. Add "invitations" to INSTALLED_APPS
+2. Add ``"invitations"`` to ``INSTALLED_APPS``:
 
    .. code-block:: python
 
@@ -27,21 +27,33 @@ Installation
             ...
         ]
 
-.. note:: **Allauth support**
+.. note:: **django-allauth support**
 
-   For allauth support ``invitations`` must come after ``allauth`` in the INSTALLED_APPS
+   For django-allauth support, ``"invitations"`` must come after ``"allauth"`` in the ``INSTALLED_APPS`` list.
 
-3. Add invitations urls to your urlpatterns:
+3. If using `django-allauth <https://docs.allauth.org/>`_, then add this configuration to your ``settings.py`` file:
+
+    .. code-block:: python
+
+        # django-allauth configuration:
+        ACCOUNT_ADAPTER = "invitations.models.InvitationsAdapter"
+
+        # django-invitations configuration:
+        INVITATIONS_ADAPTER = ACCOUNT_ADAPTER
+
+4. Add invitations URLs to your ``urlpatterns``:
 
    .. code-block:: python
 
+        from django.urls import include, path
+
         urlpatterns = [
             ...
             path("invitations/", include('invitations.urls', namespace='invitations')),
             ...
         ]
 
-4. Run migrations
+5. Run migrations:
 
     .. code-block:: sh
 

docs/usage.rst

@@ -21,17 +21,6 @@ If ``allauth`` is being used under its default settings, then two ``EmailAddress
 
 Further details can be found in the following sections.
 
-Allauth Integration
--------------------
-
-As above but note that invitations must come after allauth in the INSTALLED_APPS
-
-Set the allauth ``ACCOUNT_ADAPTER`` setting
-
-.. code-block:: python
-
-    ACCOUNT_ADAPTER = 'invitations.models.InvitationsAdapter'
-
 Sending Invites
 ---------------