Fix "always" management in add_header directive

templates/etc/nginx/sites-available/_base.j2

@@ -106,7 +106,7 @@ server {
 {% block template_headers %}
 	# --> Custom headers
 {% for key, value in __headers.iteritems() %}
-	add_header {{ key }} "{{ value }}";
+	add_header {{ key }} "{{ value | regex_replace('\s+always$', '') }}"{% if value | regex_search('\s+always$') %} always{% endif %};
 {% endfor %}
 	# <-- Custom headers
 {% endblock %}