Add ScrapingDog (#1266)

README.md

@@ -309,6 +309,7 @@ API | Description | Auth | HTTPS | CORS |
 | [Scraper.AI](https://docs.scraper.ai/#/) | Extract and monitor data from any website | `apiKey` | Yes | Unknown |
 | [ScraperApi](https://www.scraperapi.com) | Easily build scalable web scrapers | `apiKey` | Yes | Unknown |
 | [scrapestack](https://scrapestack.com/) | Real-time, Scalable Proxy & Web Scraping REST API | `apiKey` | Yes | Unknown |
+| [ScrapingDog](https://www.scrapingdog.com/) | Proxy API for Web scraping | `apiKey` | Yes | Unknown |
 | [ScreenshotAPI.net](https://screenshotapi.net/) | Create pixel-perfect website screenshots | `apiKey` | Yes | Yes |
 | [serpstack](https://serpstack.com/) | Real-Time & Accurate Google Search Results API | `apiKey` | Yes | Yes |
 | [SHOUTCLOUD](http://shoutcloud.io/) | ALL-CAPS AS A SERVICE | No | No | Unknown |