GUAC-1172: Implement file upload through object streams.

guacamole/src/main/webapp/app/client/templates/client.html

@@ -171,6 +171,7 @@
             <!-- Stationary header -->
             <div class="header">
                 <h2>{{filesystemMenuContents.name}}</h2>
+                <button class="upload button" guac-upload="uploadFiles">{{'CLIENT.ACTION_UPLOAD_FILES' | translate}}</button>
                 <button class="back" ng-click="hideFilesystemMenu()">Back</button>
             </div>