Keep the app backup list concise

if you have even more than 10 apps, the dialog overflows and makes for bad
screenshots...

src/views/backups.html

@@ -24,7 +24,9 @@
         </div>
         <br/>
         <p class="text-muted">Contains backups of {{ backupDetails.backup.contents.length }} apps:</p>
-        <p style="padding-left: 20px;" ng-repeat="app in backupDetails.backup.contents"><a ng-href="/#/app/{{app.id}}/backups">{{ app.label || app.fqdn }}</a></p>
+        <span ng-repeat="app in backupDetails.backup.contents">
+          <a ng-href="/#/app/{{app.id}}/backups">{{app.label || app.fqdn}}</a><span ng-hide="$last">,</span>
+        </span>
       </div>
       <div class="modal-footer">
         <button type="button" class="btn btn-primary" data-dismiss="modal">Close</button>