Add File Versioning to folder info (fixes #963)

Could potentially use shorter value strings ("Simple" vs "Simple File
Versioning"), but this avoid introducing unnecessary strings to
translate - can always be changed in the future.

gui/index.html

@@ -150,6 +150,13 @@
                       <th><span class="glyphicon glyphicon-refresh"></span>&emsp;<span translate>Rescan Interval</span></th>
                       <td class="text-right">{{folder.RescanIntervalS}} s</td>
                     </tr>
+                    <tr ng-if="folder.Versioning.Type">
+                      <th><span class="glyphicon glyphicon-tags"></span>&emsp;<span translate>File Versioning</span></th>
+                      <td class="text-right" ng-switch="folder.Versioning.Type">
+                        <span ng-switch-when="staggered" translate>Staggered File Versioning</span>
+                        <span ng-switch-when="simple" translate>Simple File Versioning</span>
+                      </td>
+                    </tr>
                     <tr>
                       <th><span class="glyphicon glyphicon-share-alt"></span>&emsp;<span translate>Shared With</span></th>
                       <td class="text-right">{{sharesFolder(folder)}}</td>