docs: added sponsors logos

***NO_CI***

README.md

@@ -192,9 +192,15 @@ We are looking for translators to make Wiki.js available in multiple languages.
 
 <h2 align="center">Special Thanks</h2>
 
+![Algolia](https://wiki.js.org/assets/images/logo_algolia.png)  
+[Algolia](https://www.algolia.com/) for providing access to their incredible search engine.
+
 ![Browserstack](https://wiki.js.org/assets/images/logo_browserstack.png)  
 [Browserstack](https://www.browserstack.com/) for providing access to their great cross-browser testing tools.
 
+![Cloudflare](https://wiki.js.org/assets/images/logo_cloudflare.png)  
+[Cloudflare](https://www.cloudflare.com/) for providing their great CDN, SSL and advanced networking services.
+
 [![DigitalOcean](https://wiki.js.org/assets/images/logo_digitalocean.png)](https://m.do.co/c/5f7445bfa4d0)  
 [DigitalOcean](https://m.do.co/c/5f7445bfa4d0) for providing hosting of the Wiki.js documentation site.