add an optional post-commit hook to send a commit email

tasks/etckeeper.yml

@@ -29,3 +29,9 @@
 - file: path=/etc/.bzr state=absent
 - name: "etckeeper: Initialize"
   command: etckeeper init creates=/etc/.git/
+
+- name: enable etckeeper commit mails
+  template: src=post-commit-mail.j2
+            dest=/etc/.git/hooks/post-commit
+            mode=0755
+  when: etckeeper_mailto is defined