[explorev2] using a loader to load the explorev2 specific css (#1843)

superset/assets/javascripts/explorev2/index.jsx

@@ -11,6 +11,7 @@ import { now } from '../modules/dates';
 const $ = window.$ = require('jquery'); // eslint-disable-line
 const jQuery = window.jQuery = require('jquery'); // eslint-disable-line
 require('bootstrap');
+require('./main.css');
 
 import { initialState } from './stores/store';
 

superset/assets/javascripts/explorev2/main.css

@@ -0,0 +1,22 @@
+.scrollbar-container {
+  position: relative;
+  overflow: hidden;
+  width: 100%;
+  height: 100%;
+}
+
+.scrollbar-content {
+  position: absolute;
+  top: 0px;
+  left: 0px;
+  right: 0px;
+  bottom: 0px;
+  overflow: scroll;
+  margin-right: 0px;
+  margin-bottom: 100px;
+}
+
+.fave-unfave-icon, .edit-desc-icon {
+  padding: 0 0 0 .5em;
+  font-size: 14px;
+}