Updated Satis install command.

doc/articles/handling-private-packages-with-satis.md

@@ -9,7 +9,7 @@ lightweight, static file-based version of packagist and can be used to host the
 metadata of your company's private packages, or your own. It basically acts as
 a micro-packagist. You can get it from
 [GitHub](http://github.com/composer/satis) or install via CLI:
-`composer.phar create-project composer/satis --stability=dev`.
+`php composer.phar create-project composer/satis --stability=dev --keep-vcs`.
 
 ## Setup