Fix broken images in FAQ

This relates to https://github.com/owncloud/documentation/issues/3354.

doc/faq.rst

@@ -29,18 +29,21 @@ Specifically, you have to:
 1. Remove the existing connection which syncs to the wrong directory
 2. Add a new connection which syncs to the desired directory
 
-image:: images/setup/ownCloud-remove_existing_connection.png
+.. image:: images/setup/ownCloud-remove_existing_connection.png
+   :alt: Remove an existing connection
 
 To do so, in the client UI, which you can see above, click the "**Account**" drop-down menu and then click "Remove". 
 This will display a "**Confirm Account Removal**" dialog window.
 
-image:: images/setup/ownCloud-remove_existing_connection_confirmation_dialog.png
+.. image:: images/setup/ownCloud-remove_existing_connection_confirmation_dialog.png
+   :alt: Remove existing connection confirmation dialog
 
 If you're sure, click "**Remove connection**".
 
 Then, click the Account drop-down menu again, and this time click "**Add new**".
 
-image:: images/setup/ownCloud-replacement_connection_wizard.png
+.. image:: images/setup/ownCloud-replacement_connection_wizard.png
+   :alt: Replacement connection wizard
 
 This opens the ownCloud Connection Wizard, which you can see above, *but* with an extra option.
 This option provides the ability to either: keep the existing data (synced by the previous connection) or to start a clean sync (erasing the existing data).