fix issue 290

Author: galvisgilberto

plotly/plotly_offline_aux/plotlyoffline.m

@@ -61,7 +61,7 @@
                       id, link_text);
 
     plotly_script = sprintf(['\n<div class="%s loading" style=', ...
-                              'color: rgb(50,50,50);">Drawing...</div>' ... 
+                              'color: rgb(50,50,50);"> </div>' ... 
                               '\n<div id="%s" style="height: %s;',...
                              'width: %s;" class="plotly-graph-div">' ...
                              '</div> \n<script type="text/javascript">' ...