btop: Install btop and run it on the console

`btop` is so much better than `top`.  It makes a really nice status
indicator for machine health, so I like running it on tty1.

roles/btop/tasks/main.yml

@@ -0,0 +1,53 @@
+- name: ensure btop is installed
+  package:
+    name: btop
+    state: present
+  tags:
+  - install
+
+- name: ensure btop systemd unit is installed
+  copy:
+    src: btop.service
+    dest: /etc/systemd/system/btop.service
+    owner: root
+    group: root
+    mode: u=rw,go=r
+  notify:
+  - reload systemd
+  - restart btop
+  tags:
+  - systemd
+
+- name: ensure btop configuration directory exists
+  file:
+    path: /etc/btop
+    owner: root
+    group: root
+    mode: u=rwx,go=rx
+    state: directory
+  tags:
+  - config
+- name: ensure btop is configured
+  template:
+    src: btop.conf.j2
+    dest: /etc/btop/btop.conf
+    owner: root
+    group: root
+    mode: u=rw,go=r
+  notify:
+  - restart btop
+  tags:
+  - config
+
+- name: ensure btop service is enabled
+  service:
+    name: btop
+    enabled: true
+  tags:
+  - service
+
+- meta: flush_handlers
+- name: ensure btop service is running
+  service:
+    name: btop
+    state: started