Setup mailman3 server

We want to migrate to mailman3 as mailman2 is basically unmaintained and requires Python 2 which is EOL.

Because the mailman and mailman3 packages conflict and we don't want to perform a big bang migration, mailman3 must be deployed on a separate server. mailman-web (mailman3's web interface) hasn't been packaged yet, so for now we are using my homebrewed PKGBUILD.

[1] https://gist.github.com/klausenbusk/5982063f95c503754a51ed2fefb8915e

Ref #59 (closed)

---

Migrated lists:

• arch-announce
• arch-devops-private
• arch-events
• arch-wiki-admins

roles/nginx/tasks/main.yml

@@ -27,6 +27,7 @@
 
 - name: install cert renewal hook
   template: src=letsencrypt.hook.d.j2 dest=/etc/letsencrypt/hook.d/nginx owner=root group=root mode=0755
+  when: "'certbot' in ansible_play_role_names"
 
 - name: create nginx.d directory
   file: state=directory path=/etc/nginx/nginx.d owner=root group=root mode=0755