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/README.md

@@ -0,0 +1,29 @@
+# MediaCMS Web Client (demo)
+
+### **Requirements**
+
+- nodejs: version >= 14.17.0
+
+---
+
+### **Installation**
+
+    npm install
+
+---
+
+### **Development**
+
+    npm run start
+
+Open in browser: [http://localhost:8088](http://localhost:8088)
+
+---
+
+### **Build**
+
+    npm run dist
+
+Generates the folder "**_frontend/dist_**".
+
+Copy folders and files from "**_frontend/dist/static_**" into "**_static_**".