restructure

update readme
fix ansible role tags

ansible/roles/nsd/tasks/main.yml

@@ -0,0 +1,18 @@
+- name: Install nsd
+  apt:
+    name: nsd
+- name: Copy nsd.conf
+  copy:
+    src: "{{ role_path }}/files/nsd.conf"
+    dest: /etc/nsd/nsd.conf
+  register: config
+- name: Copy zone directory
+  copy:
+    src: "{{ role_path }}/files/zones"
+    dest: /etc/nsd
+  register: zones
+- name: Enable nsd
+  systemd:
+    name: nsd
+    enabled: true
+    state: "{{ 'restarted' if config.changed or zones.changed else 'started' }}"