Add guide for archiving mailing lists

Signed-off-by: Michal Konecny <mkonecny@redhat.com>

modules/howtos/pages/archive_list.adoc

@@ -0,0 +1,26 @@
+= How to archive mailing list
+
+[NOTE]
+====
+You need to be mailman admin to be able to follow this guide.
+====
+
+. Go to the link:https://lists.fedoraproject.org/admin/lists/[mailman site]
+on the top right corner select `Sign In`
++
+Do not login through the username and password fields, login using the
+third party `Fedora` link to assume fas permissions
++
+. Find the mailing list you want to archive and click on it
+
+. Set settings -> list identity -> to have [ARCHIVED] at the end of the display name
+
+. Save changes
+
+. Set settings -> message acceptance -> reject with notification (you need to do this twice)
+
+. Save changes
+
+. Set settings -> subscription policy -> confirm then moderate
+
+. Save changes