Huobi integration

[minicheddar]

Add support for Huobi cryptocurrency exchange

• Implement spot trade detail stream
  https://huobiapi.github.io/docs/spot/v1/en/#trade-detail

• Implement spot market by price stream
  https://huobiapi.github.io/docs/spot/v1/en/#market-by-price-refresh-update

• Implement futures trade detail stream
  https://huobiapi.github.io/docs/dm/v1/en/#subscribe-trade-detail-data

• Implement futures market depth stream
  https://huobiapi.github.io/docs/dm/v1/en/#subscribe-incremental-market-depth-data

[minicheddar]

Spot implemented, parking futures for now