Add TODO stub of Pi Hole setup

See the TODO comment in /roles/pi-hole/tasks/main.yml.
We'll probably need to install other software first.

roles/pi-hole/tasks/main.yml

@@ -0,0 +1,9 @@
+---
+- name: Install Podman
+  become: true
+  ansible.builtin.apt:
+    name: podman
+    state: present
+# TODO: I'll have to come back to this configuration, it appears there's a problem.
+#       We're going to need to reuse web ports in order to serve multiple websites from
+#       the Raspberry Pi, this will probably necesitate installing Nginx or another reverse proxy.