Frontent dev env (#247)

* Added frontend development files/environment

* More items-categories related removals

* Improvements in pages templates (inc. static pages)

* Improvements in video player

* Added empty home page message + cta

* Updates in media, playlist and management pages

* Improvements in material icons font loading

* Replaced media & playlists links in frontend dev-env

* frontend package version update

* chnaged frontend dev url port

* static files update

* Changed default position of theme switcher

* enabled frontend docker container

frontend/src/static/js/components/MediaMultiListWrapper.tsx

@@ -0,0 +1,14 @@
+import React from 'react';
+import './MediaListWrapper.scss';
+
+interface MediaMultiListWrapperProps {
+  className?: string;
+  style?: { [key: string]: any };
+  children?: any;
+}
+
+export const MediaMultiListWrapper: React.FC<MediaMultiListWrapperProps> = ({ className, style, children }) => (
+  <div className={(className ? className + ' ' : '') + 'media-list-wrapper'} style={style}>
+    {children || null}
+  </div>
+);