ux(panel menu): changed remove icon to trash icon, closes #3939

public/app/features/panel/panel_menu.js

@@ -37,7 +37,7 @@ function (angular, $, _) {
           template += '<div class="panel-menu-row">';
           template += '<a class="panel-menu-icon pull-left" ng-click="ctrl.updateColumnSpan(-1)"><i class="fa fa-minus"></i></a>';
           template += '<a class="panel-menu-icon pull-left" ng-click="ctrl.updateColumnSpan(1)"><i class="fa fa-plus"></i></a>';
-          template += '<a class="panel-menu-icon pull-right" ng-click="ctrl.removePanel()"><i class="fa fa-remove"></i></a>';
+          template += '<a class="panel-menu-icon pull-right" ng-click="ctrl.removePanel()"><i class="fa fa-trash"></i></a>';
           template += '<div class="clearfix"></div>';
           template += '</div>';
         }