Clone this repo

I was confused where to run make command because it was no clone instructions for this repository.

This MR add section with 2 commands: clone repo and cd into it. I think it will be more user-friendly

README.md

@@ -44,6 +44,13 @@ TODO
 TODO
+### Clone GitLab Development Kit repository
+
+```
+git clone https://gitlab.com/gitlab-org/gitlab-development-kit.git
+cd gitlab-development-kit
+```
+
 ### Install the repositories and gems
 The Makefile will clone the repositories, install the Gem bundles and set up