Add playlists feature (#871)

* Open multi-file torrents as playlists

* Add `repeat` and `shuffle` options to the player

* Autoplay first file in torrent

* replaces `pickFileToPlay` feature
* when reopening player, restores the most recently viewed file

* Add playlist navigation buttons to Windows thumbar

* Remove `repeat` and `shuffle` options

This reverts commit 9284122461.

* Play files in order they appear in torrent

* Clean up playlists code

src/main/ipc.js

@@ -64,6 +64,11 @@ function init () {
     thumbar.enable()
   })
 
+  ipc.on('onPlayerUpdate', function (e, ...args) {
+    menu.onPlayerUpdate(...args)
+    thumbar.onPlayerUpdate(...args)
+  })
+
   ipc.on('onPlayerClose', function () {
     menu.setPlayerOpen(false)
     powerSaveBlocker.disable()