Merge branch 'docs-admin-imgs' into 'master'

Docs: audit/auditor docs images

See merge request gitlab-org/gitlab-ce!30450

doc/administration/audit_events.md

@@ -99,7 +99,7 @@ It is possible to filter particular actions by choosing an audit data type from
 the filter drop-down. You can further filter by specific group, project or user
 (for authentication events).
 
-![audit log](audit_log.png)
+![audit log](img/audit_log.png)
 
 ### Missing events
 

doc/administration/auditor_users.md

@@ -52,7 +52,7 @@ section.
    **Admin Area > Users**. You will find the option of the access level under
    the 'Access' section.
 
-    ![Admin Area Form](auditor_access_form.png)
+    ![Admin Area Form](img/auditor_access_form.png)
 
 1. Click **Save changes** or **Create user** for the changes to take effect.