[fix] Fix the issue alias_traversal (#45)

* Fix the issue alias_traversal

https://github.com/yandex/gixy/blob/master/docs/en/plugins/aliastraversal.md

* Update fix alias_traversal

* Don't change original nginx conf file and add change_url

* Use newest version of ynh_add_nginx_config from #462
No more need to deal with "#sub_path_only"

* Revert "Use newest version of ynh_add_nginx_config from #462" as it's not released (and subject to discussions)!

This reverts commit fac62c49ff.

* Fix indentation

conf/nginx.conf

@@ -1,4 +1,5 @@
-location __PATH__ {
+#sub_path_only rewrite ^__PATH__$ __PATH__/ permanent;
+location __PATH__/ {
 
   # Path to source
   alias __FINALPATH__/ ;