remote.php :: use non apache-only env vars

- fixes following error when using nginx + php-fpm

[error] *6568 FastCGI sent in stderr: "PHP message:
PHP Warning:  strpos(): Offset not contained in string in
/some-path/owncloud/remote.php on line 10"

Signed-off-by: BlackEagle <ike.devolder@gmail.com>