fix logo on base_url prefix

IPython/html/static/notebook/js/kernelselector.js

@@ -133,7 +133,7 b' define(['
         this.events.on('spec_changed.Kernel', function(event, data) {
             that.current_selection = data.name;
             that.element.find("#current_kernel_spec").find('.kernel_name').text(data.display_name);
-            that.element.find("#current_kernel_logo").attr("src", "/kernelspecs/"+data.name+"/logo-64x64.png");
+            that.element.find("#current_kernel_logo").attr("src", that.notebook.base_url+"kernelspecs/"+data.name+"/logo-64x64.png");
         });
 
         this.events.on('kernel_created.Session', function(event, data) {