refactored BeatsHttp to a manager, refactored Json logic to JsonEngine. Fixed GenreGetById bug (need clientId and not token).
Merge remote-tracking branch 'upstream/master'

Conflicts:
	CodingChick.BeatsMusicAPI/CodingChick.BeatsMusicAPI.Core/Base/BeatsMusicManager.cs
	CodingChick.BeatsMusicAPI/CodingChick.BeatsMusicAPI.Core/BeatsMusicClient.cs
	CodingChick.BeatsMusicAPI/CodingChick.BeatsMusicAPI.Core/Endpoints/PlaylistsEndpoint.cs