Bittrex v3 API support broke `ws-orderbook` and `ws-ticker`

[EcBen]

@jjxtra @onurselcuk
The recent change in Pull Request #587 broke the ExchangeSharpConsole for ws-orderbook and ws-ticker:

exchange-sharp.exe ws-orderbook -e bittrex -s ETH-BTC
Connecting web socket to Bittrex...
Press CTRL-C or Q to quit
https://api.bittrex.com/v3/markets
...

nothing happens.

exchange-sharp.exe ws-tickers -e bittrex -s ETH-BTC
Connecting web socket to Bittrex...
Press CTRL-C or Q to quit
https://api.bittrex.com/v3/markets
Web socket connected.

nothing happens.

[EcBen]

@onurselcuk Thanks! It's working for me now after your latest change.