added Coin API

README.md

@@ -153,6 +153,7 @@ API | Description | Auth | HTTPS | CORS | Link |
 | Bitfinex | Cryptocurrency Trading Platform | `apiKey` | Yes | Unknown | [Go!](https://docs.bitfinex.com/docs/introduction) |
 | Block | Bitcoin Payment, Wallet & Transaction Data | `apiKey` | Yes | Unknown | [Go!](https://www.block.io/docs/basic) |
 | Blockchain | Bitcoin Payment, Wallet & Transaction Data | No | Yes | Unknown | [Go!](https://www.blockchain.info/api) |
+| CoinAPI | All Currency Exchanges integrate under a single api | `apiKey` | Yes | No | [Go!](https://docs.coinapi.io/) |
 | Coinbase | Bitcoin, Litecoin and Ethereum Prices | `apiKey` | Yes | Unknown | [Go!](https://developers.coinbase.com) |
 | CoinBin | Cryptocurrency information | No | Yes | Unknown | [Go!](https://coinbin.org/) |
 | CoinDesk | Bitcoin Price Index | No | No | Unknown | [Go!](http://www.coindesk.com/api/) |