nginx - disable apache from starting on boot if present

Or there might be a race for port 80 on reboot

roles/nginx/tasks/install.yml

@@ -2,6 +2,7 @@
   systemd:
     name: "{{ apache_service }}"    # apache2 or httpd, per /opt/iiab/iiab/vars/<OS>.yml
     state: stopped
+    enabled: no
   ignore_errors: yes
   # 'when: apache_installed is defined' insuff b/c mysql's php (etc) can install apache2