TrackAudioAnalysis is missing track info

[Peaj]

The TrackAudioAnalysis class is missing the track info e.g. "key" and "key_confidence".

From the Spotify Web API documentation:

"track": {
        "duration": 255.34898,
        "sample_md5": "",
        "offset_seconds": 0,
        "window_seconds": 0,
        "analysis_sample_rate": 22050,
        "analysis_channels": 1,
        "end_of_fade_in": 0,
        "start_of_fade_out": 251.73333,
        "loudness": -11.84,
        "tempo": 98.002,
        "tempo_confidence": 0.423,
        "time_signature": 4,
        "time_signature_confidence": 1,
        "key": 5,
        "key_confidence": 0.36,
        "mode": 0,
        "mode_confidence": 0.414,
        "codestring": "eJxVnAmS5DgOBL-ST-B9_P9j4x7M6qoxW9tpsZQSCeI...",
        "code_version": 3.15,
        "echoprintstring": "eJzlvQmSHDmStHslxw4cB-v9j_A-tahhVKV0IH9...",
        "echoprint_version": 4.12,
        "synchstring": "eJx1mIlx7ToORFNRCCK455_YoE9Dtt-vmrKsK3EBsTY...",
        "synch_version": 1,
        "rhythmstring": "eJyNXAmOLT2r28pZQuZh_xv7g21Iqu_3pCd160xV...",
        "rhythm_version": 1
    }