Refactor dialogs, make it simple to add a new dialog to all views

ui/src/artist/ArtistList.js

@@ -17,7 +17,6 @@ import FavoriteIcon from '@material-ui/icons/Favorite'
 import FavoriteBorderIcon from '@material-ui/icons/FavoriteBorder'
 import { makeStyles } from '@material-ui/core/styles'
 import { useDrag } from 'react-dnd'
-import { AddToPlaylistDialog } from '../dialogs'
 import {
   ArtistContextMenu,
   List,
@@ -32,7 +31,6 @@ import {
 import config from '../config'
 import ArtistListActions from './ArtistListActions'
 import { DraggableTypes } from '../consts'
-import DownloadMenuDialog from '../dialogs/DownloadMenuDialog'
 
 const useStyles = makeStyles({
   contextHeader: {
@@ -178,8 +176,6 @@ const ArtistList = (props) => {
       >
         <ArtistListView {...props} />
       </List>
-      <AddToPlaylistDialog />
-      <DownloadMenuDialog />
     </>
   )
 }