Add Chevereto to free self-hosted software (#3429)

Chevereto has a new free edition, repository is at https://github.com/chevereto/chevereto

README.md

@@ -1550,6 +1550,7 @@ _Related: [Monitoring](#monitoring), [Bookmarks and Link Sharing](#bookmarks-and
 
 A [gallery](https://en.wikipedia.org/wiki/Gallery_Software) is software that helps the user publish or share photos, pictures, videos or other digital media.
 
+- [Chevereto](https://github.com/chevereto/chevereto) - Ultimate image sharing software. Create your very own personal image hosting website in just minutes. ([Source Code](https://github.com/chevereto/chevereto)) `AGPL-3.0` `PHP`
 - [Coppermine](https://coppermine-gallery.net/) - Multilingual photo gallery that integrates with various bulletin boards. Includes upload approval and password protected albums. ([Demo](https://coppermine-gallery.net/demo/cpg15x/), [Source Code](https://github.com/coppermine-gallery/cpg1.6.x)) `GPL-3.0` `PHP`
 - [Damselfly](https://damselfly.info) - Fast server-based photo management system for large collections of images. Includes face detection, face & object recognition, powerful search, and EXIF Keyword tagging. Runs on Linux, MacOS and Windows. `GPL-3.0` `C#/.NET`
 - [Fussel](https://github.com/cbenning/fussel) - Fussel is a static photo gallery generator. Easily generate a reactive gallery and host the optimized static folder of assets. `MIT` `Python`