Fixes to make spinners in cluster list display correctly.

IPython/html/static/tree/js/clusterlist.js

@@ -104,7 +104,7 b' var IPython = (function (IPython) {'
         var input = $('<input/>').attr('type','number')
                 .attr('min',1)
                 .attr('size',3)
-                .addClass('engine_num_input');
+                .addClass('engine_num_input form-control');
         engines_col.append(input);
         var start_button = $('<button/>').addClass("btn btn-default btn-xs").text("Start");
         var action_col = $('<div/>').addClass('action_col col-md-2').append(

IPython/html/static/tree/less/tree.less

@@ -78,7 +78,6 b' ul.breadcrumb {'
     padding-bottom: @dashboard_tb_pad;
     padding-left: @dashboard_lr_pad;
     padding-right: @dashboard_lr_pad;
-    height: @btn_mini_height;
     line-height: @btn_mini_height;
 }
 
@@ -106,7 +105,7 b' input.nbname_input, input.engine_num_input {'
     // These settings give these inputs a height that matches @btn_mini_height = 22
     padding-top: 3px;
     padding-bottom: 3px;
-    height: 14px;
+    height: @btn_mini_height;
     line-height: 14px;
     margin: 0px;
 }

IPython/html/templates/tree.html

@@ -75,7 +75,7 b' data-notebook-path="{{notebook_path}}"'
         </div>
 
         <div id="running_list">
-            <div id="running_list_header" class="row list_header"> 
+            <div id="running_list_header" class="row warning"> 
                 <div> There are no notebooks running. </div>
             </div> 
         </div>