Add docs for accessing a migrated site

docs/access_migrated_site.md

+<div data-theme-toc="true"> </div>
+
+# Accessing a migrated site
+
+The default URL to access your migrated site is: `migrate-sitename.webtest.cern.ch`.
+
+A drupal site is connected with an OpenShift project. You can find your migrated sites in the OpenShift console by following a few simple steps.
+
+#### 1. Go to the [OpenShift console](https://drupal.cern.ch) page
+
+Check on the left side menu that the **Administrator** option is selected (and **not** Developer).
+
+You will see a list of OpenShift projects. Each migrated site is connected with an OpenShift project.
+
+![Screenshot](images/openshift_console-projects_list.png)
+
+---
+
+#### 2. Click on `Installed Operators` on the left side menu
+
+Make sure that you are in the correct `Project`. At first you will see a message "No Operators Found". Please wait a couple of minutes until the "DrupalSite Operator" appears as shown in the screenshot below. 
+
+![Screenshot](images/openshift_console-installed_operators.png)
+
+---
+
+#### 3. Click on `Create Drupal website` on the latest DrupalSite Operator
+
+![Screenshot](images/openshift_console-installed_operators_create_drupal_website.png)
+
+---
+
+#### 4. View your sites
+
+Related sites for different environments (production, development, test) are grouped under the same project.
+
+![Screenshot](images/openshift_console-drupalsites_list.png)