Add items in the same player of the playlist

[regseb]

Describe

When you send a SoundCloud playlist to the Kodi video player, the addon adds the items to the music player. The items should be added in the same player of the playlist.
It would allow to create playlists from YouTube videos and SoundCloud music by sending everything in the player video.

To Reproduce

1. In Kodi, Allow remote control via HTTP (Settings / Services / Control).
2. Execute (by changing the IP address): curl -d '{ "jsonrpc": "2.0", "method": "Playlist.Clear", "params": { "playlistid": 1 }, "id": 1 }' -H 'Content-type: application/json' -X POST 127.0.0.1:8080/jsonrpc
3. Execute (by changing the IP address): curl -d '{ "jsonrpc": "2.0", "method": "Playlist.Add", "params": { "playlistid": 1, "item": { "file": "plugin://plugin.audio.soundcloud/play/?url=https%3A%2F%2Fsoundcloud.com%2Fdubioza-kolektiv%2Fsets%2Fdubioza-remixed" } }, "id": 2 }' -H 'Content-type: application/json' -X POST 127.0.0.1:8080/jsonrpc
4. Execute (by changing the IP address): curl -d '{ "jsonrpc": "2.0", "method": "Player.Open", "params": { "item": { "playlistid": 1 } }, "id": 3 }' -H 'Content-type: application/json' -X POST 127.0.0.1:8080/jsonrpc

Expected Behavior

The musics are in the video player.

Actual Behavior

The musics are in the music player.