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

defaults/main.yml

@@ -32,13 +32,7 @@ nginx_helper_dir: '{{ nginx_etc_dir}}/helper'
 #
 
 # PHP
-nginx_php56: false
-nginx_php70: false
-nginx_php56_sockets:
-  - unix_socket: "/run/php5-fpm.sock"
-nginx_php70_sockets:
-  - unix_socket: "/run/php/php7.0-fpm.sock"
-nginx_upstreams: []
+nginx_php: []
 
 #
 # Nginx configuration