New PHP management

- New versions (7.x)
- PHP upstream name
- Sites can use : default PHP version, select first one by PHP version,
  select by upstream name
- Add PHP filter plugin

vars/main.yml

@@ -43,6 +43,3 @@ nginx_servers_default_headers:
   'X-Frame-Options': 'DENY always'
   'X-Content-Type-Options': 'nosniff always'
   'X-XSS-Protection': '1; mode=block'
-
-nginx_upstream_php56: 'php56'
-nginx_upstream_php70: 'php70'