Add IP bans

Users can be banned by IP address now, either by singular IP or in an IP
range. If they are banned and attempt to post, they will be met with a
"you are banned until X date" screen.

There are a few loose threads with this, and IP bans may be obsolete if
I decide to go the accounts-required-for-posting route. But I think this
is a good start for 4chan style posting.

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>

board/urls.py

@@ -16,6 +16,11 @@ urlpatterns = [
         TemplateView.as_view(template_name="board/report_success.html"),
         name="report_success",
     ),
+    path(
+        "banned",
+        BannedView.as_view(),
+        name="banned",
+    ),
 ]
 # TODO - make this conditional so we can serve images up with whatever server we want
 urlpatterns += static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)