Fix link of Bitfinex API (#1044)

README.md

@@ -172,7 +172,7 @@ API | Description | Auth | HTTPS | CORS |
 | [Binance](https://github.com/binance-exchange/binance-official-api-docs) | Exchange for Trading Cryptocurrencies based in China | `apiKey` | Yes | Unknown |
 | [BitcoinAverage](https://apiv2.bitcoinaverage.com/) | Digital Asset Price Data for the blockchain industry | `apiKey` | Yes | Unknown |
 | [BitcoinCharts](https://bitcoincharts.com/about/exchanges/) | Financial and Technical Data related to the Bitcoin Network | No | Yes | Unknown |
-| [Bitfinex](https://docs.bitfinex.com/docs/introduction) | Cryptocurrency Trading Platform | `apiKey` | Yes | Unknown |
+| [Bitfinex](https://docs.bitfinex.com/docs/getting-started) | Cryptocurrency Trading Platform | `apiKey` | Yes | Unknown |
 | [Bitmex](https://www.bitmex.com/app/apiOverview) | Real-Time Cryptocurrency derivatives trading platform based in Hong Kong | `apiKey` | Yes | Unknown |
 | [Bittrex](https://bittrex.com/Home/Api) | Next Generation Crypto Trading Platform | `apiKey` | Yes | Unknown |
 | [Block](https://www.block.io/docs/basic) | Bitcoin Payment, Wallet & Transaction Data | `apiKey` | Yes | Unknown |