Change icon on active menu item (#903)

* add icons

* add logic to change the icon

* make the active menu bold

* Encapsulate the dynamic icon behaviour into a self-contained component

Co-authored-by: Deluan <deluan@navidrome.org>

ui/src/album/index.js

@@ -1,9 +1,7 @@
-import AlbumIcon from '@material-ui/icons/Album'
 import AlbumList from './AlbumList'
 import AlbumShow from './AlbumShow'
 
 export default {
   list: AlbumList,
   show: AlbumShow,
-  icon: AlbumIcon,
 }