#719 uploader spinner fix

template/uploader_nested_form_wrapper.html

@@ -1,6 +1,6 @@
 <div id="bx-uploader-file-{storage_object}-{file_id}" class="bx-uploader-ghost">
     <div class="bx-uploader-ghost-preview bx-def-padding-right bx-def-padding-top">
-        <img src="{file_icon}" class="bx-def-border" />
+        <img src="{file_icon}" class="bx-def-border" onload="$(this).css('background-image', 'url()')" />
     </div>
     <div class="bx-uploader-ghost-form ">
         <div class="bx-uploader-ghost-form-filename bx-def-padding-top bx-def-padding-bottom bx-def-font-grayed">{file_name}</div>