added info about GitHub importing

doc/workflow/importing/import_projects_from_github.md

@@ -3,6 +3,8 @@
 It takes just a couple of steps to import your existing GitHub projects to GitLab. Keep in mind that it is possible only if
 GitHub support is enabled on your GitLab instance. You can read more about GitHub support [here](http://doc.gitlab.com/ce/integration/github.html)
 
+You can import your existing GitHub Enterprise projects following these same steps. You'll also need to [enable GitHub Enterprise support](http://doc.gitlab.com/ee/integration/github.html) on your GitLab instance.
+
 * Sign in to GitLab.com and go to your dashboard.
 * To get to the importer page, you need to go to the "New project" page.