add playbook for matrix.archlinux.org

playbooks/matrix.archlinux.org.yml

+---
+
+- name: setup matrix
+  hosts: matrix.archlinux.org
+  remote_user: root
+  roles:
+    - { role: common }
+    - { role: tools }
+    - { role: firewalld }
+    - { role: sshd }
+    - { role: root_ssh }
+    - { role: unbound }
+    - { role: borg-client }
+    - { role: certbot }
+    - { role: nginx }
+    - role: postgres
+      postgres_shared_buffers: 500MB
+      postgres_work_mem: 32MB
+      postgres_maintenance_work_mem: 1GB
+      postgres_effective_cache_size: 1GB
+    - { role: matrix, tags: ['matrix'] }