Update Coinbase Auth

README.md

@@ -149,7 +149,7 @@ API | Description | Auth | HTTPS | Link |
 API | Description | Auth | HTTPS | Link |
 |---|---|---|---|---|
 | Blockchain | Bitcoin Payment, Wallet & Transaction Data | No | Yes | [Go!](https://www.blockchain.info/api) |
-| Coinbase | Bitcoin, Litecoin and Ethereum Prices | No | Yes | [Go!](https://developers.coinbase.com) |
+| Coinbase | Bitcoin, Litecoin and Ethereum Prices | `apiKey` | Yes | [Go!](https://developers.coinbase.com) |
 | CoinBin | Cryptocurrency information | No | Yes | [Go!](https://coinbin.org/) |
 | CoinDesk | Bitcoin Price Index | No | No | [Go!](http://www.coindesk.com/api/) |
 | CoinMarketCap | Cryptocurrencies Prices | No | Yes | [Go!](https://coinmarketcap.com/api/) |