File2: clarified presentation of file upload progress indicator in sidebar

vispa/extensions/file2/static/html/view/upload.html

 <div>
-  <h3><i class="fa fa-upload"></i>File Upload</h4>
+  <h3><i class="fa fa-upload"></i>Upload Progress</h4>
   <item v-for="(i, j) in jobs" :job="j"></item>
 </div>

vispa/extensions/file2/static/html/vue/uploaditem.html

 <div class="item" :title="title">
-  <h4 v-show="count === 0"><i>No file selected</i></h4>
   <h4 v-show="count === 1">{{names[0]}}</h4>
   <h4 v-show="count > 1"><i>{{count}} files</i></h4>
   <div class="probar" v-show="total">