Patch from issue 975 on behalf of Phil: "Proposition of a patch right Pannel (new visual rendering <-> icons instead of text)"

It moreover better handle workflow changes: no need to restart RT for some options.

rtgui/batchtoolpanelcoord.cc

@@ -35,6 +35,8 @@ BatchToolPanelCoordinator::BatchToolPanelCoordinator (FilePanel* parent) : ToolP
 	if (ipi!=toolPanels.end())
 		toolPanels.erase (ipi);
 	toolPanelNotebook->remove_page (*metadataPanel);
+	metadataPanel = 0;
+	toiM = 0;
 
     for (int i=0; i<toolPanels.size(); i++)
         toolPanels[i]->setBatchMode (true);