touch htpasswd file if it doesn't exist

Fixes #70

nginx/users.sls

@@ -5,6 +5,10 @@ htpasswd:
   pkg.installed:
     - name: {{ nginx.apache_utils }}
 
+make sure {{ htauth }} exists:
+  file.exists:
+    - name: {{ htauth }}
+
 {% for name, user in pillar.get('users', {}).items() %}
 {% if user['webauth'] is defined -%}
 
@@ -18,4 +22,4 @@ nginx_user_{{name}}:
       - pkg: htpasswd
 
 {% endif -%}
-{% endfor %}
+{% endfor %}