Code the WS Method 'UpdateYoutubeCustomPlaylist'

[Rayanox]

This method's goal is to update the custom playlist to retrieve the new content on Youtube based on the algorithm decided in a composer class. The composer class goal is to define all the different ways to create a playlist (ex: 3 videos of new musics, then 3 videos of news, then 1 documentary video..).

The playlist method declaration is like:

• UpdateYoutubeCustomPlaylist(String code)
  with code = the code of the algorithm of this custom playlist model.