added link to GitLab Basics

doc/README.md

@@ -4,6 +4,7 @@
 
 - [API](api/README.md) Automate GitLab via a simple and powerful API.
 - [GitLab as OAuth2 authentication service provider](integration/oauth_provider.md). It allows you to login to other applications from GitLab.
+- [GitLab Basics](gitlab_basics/README.md) Find step by step how to start working on your commandline and on GitLab.
 - [Importing to GitLab](workflow/importing/README.md).
 - [Markdown](markdown/markdown.md) GitLab's advanced formatting system.
 - [Permissions](permissions/permissions.md) Learn what each role in a project (guest/reporter/developer/master/owner) can do.