Set up SpamAssassin

Scan incoming and outgoing email for spam. Use a local Unbound for DNS,
so we don't run into blocks for RBL queries.

cookbooks/unbound/kitchen.dokken.yml

@@ -0,0 +1,56 @@
+---
+driver:
+  name: dokken
+  privileged: true
+  chef_version: <%= ENV['CHEF_VERSION'] || 'current' %>
+
+transport:
+  name: dokken
+
+provisioner:
+  name: dokken
+
+platforms:
+  - name: centos-7
+    driver:
+      image: dokken/centos-7
+      pid_one_command: /usr/lib/systemd/systemd
+
+  - name: centos-stream-8
+    driver:
+      image: dokken/centos-stream-8
+      pid_one_command: /usr/lib/systemd/systemd
+
+  - name: fedora-latest
+    driver:
+      image: dokken/fedora-latest
+      pid_one_command: /usr/lib/systemd/systemd
+
+  - name: ubuntu-18.04
+    driver:
+      image: dokken/ubuntu-18.04
+      pid_one_command: /bin/systemd
+      intermediate_instructions:
+        - RUN /usr/bin/apt-get update
+
+  - name: ubuntu-20.04
+    driver:
+      image: dokken/ubuntu-20.04
+      pid_one_command: /bin/systemd
+      intermediate_instructions:
+        - RUN /usr/bin/apt-get update
+
+  - name: debian-10
+    driver:
+      image: dokken/debian-10
+      pid_one_command: /bin/systemd
+      intermediate_instructions:
+        - RUN /usr/bin/apt-get update
+
+  - name: debian-11
+    driver:
+      image: dokken/debian-11
+      pid_one_command: /bin/systemd
+      intermediate_instructions:
+        - RUN /usr/bin/apt-get update
+...