Websocket API depth with level doesn't work

[mirxak]

Hi! binance-api version 1.0.9
I found an error with BinanceWebSocketAdapterDepth which you're using in BinanceApi.websocketDepth{level} methods. BinanceWebSocketAdapterDepth uses BinanceEventDepthUpdate which parses the event message from socket but response for @Depth{levels} is another than for @Depth and NullPointerExceptions are occured. I think you can make an another BinanceEventDepthUpdate and BinanceWebSocketAdapterDepth for using in websocketDepth methods.