Add 7timer! Weather Api (#876)

* Add 7timer! Weather Api

* Add 7timer! Weather Api, Fix sorting errors

* Link to the documentation

README.md

@@ -847,6 +847,7 @@ API | Description | Auth | HTTPS | CORS |
 ### Weather
 API | Description | Auth | HTTPS | CORS |
 |---|---|---|---|---|
+| [7Timer!](http://www.7timer.info/doc.php?lang=en) | Weather, especially for Astroweather | No | No | Unknown |
 | [APIXU](https://www.apixu.com/doc/request.aspx) | Weather | `apiKey` | Yes | Unknown |
 | [Dark Sky](https://darksky.net/dev/) | Weather | `apiKey` | Yes | No |
 | [MetaWeather](https://www.metaweather.com/api/) | Weather | No | Yes | No |