thunderbird: Initial version of role

Only disables saving passwords for now.

roles/thunderbird/files/foo.sh.js

@@ -0,0 +1,2 @@
+// set defaults but allow user to change
+pref("signon.rememberSignons", false);

roles/thunderbird/tasks/main.yml

@@ -0,0 +1,13 @@
+---
+- name: install packages
+  package:
+    name: thunderbird
+    state: installed
+
+- name: install default settings
+  copy:
+    dest: /usr/lib64/thunderbird/defaults/pref/00-foo.sh.js
+    src: foo.sh.js
+    mode: 0644
+    owner: root
+    group: "{{ ansible_wheel }}"