Add image-charts API (#1004)

* feat: add image-charts

Co-authored-by: Yann Bertrand <5855339+yannbertrand@users.noreply.github.com>

README.md

@@ -260,6 +260,7 @@ API | Description | Auth | HTTPS | CORS |
 | [Gitter](https://developer.gitter.im/docs/welcome) | Chat for Developers | `OAuth` | Yes | Unknown |
 | [HTTP2.Pro](https://http2.pro/doc/api) | Test endpoints for client and server HTTP/2 protocol support | No | Yes | Unknown |
 | [IBM Text to Speech](https://console.bluemix.net/docs/services/text-to-speech/getting-started.html) | Convert text to speech | `apiKey` | Yes | Yes |
+| [Image-Charts](https://documentation.image-charts.com/) | Generate charts, QR codes and graph images | No | Yes | Yes |
 | [import.io](http://api.docs.import.io/) | Retrieve structured data from a website or RSS feed | `apiKey` | Yes | Unknown |
 | [IPify](https://www.ipify.org/) | A simple IP Address API | No | Yes | Unknown |
 | [IPinfo](https://ipinfo.io/developers) | Another simple IP Address API | No | Yes | Unknown |