Document the light git-clone (issue #294).

[skip ci]

README.md

@@ -26,6 +26,23 @@ Dependencies
 
 ---
 
+Cloning the project
+============
+
+The project git binary objects are heavy (it can take up to ~ 1.5 Gio of data). If your connection is unstable don't download the whole history (using the ``--depth`` option -- issue #294).
+
+```
+git clone git@gitlab.inria.fr:faustgrp/faust.git --depth=1 --single-branch faust
+```
+**NOTE**: you can also use the [https://gitlab.inria.fr/faustgrp/faust.git](https://gitlab.inria.fr/faustgrp/faust.git) URL.
+
+Then if you really need the full git history to work on the project, fetch it (preferably when your Internet connection is good) :
+
+```
+git fetch --unshallow
+```
+
+---
 Quick build on UNIX
 =====================