Changed LittleLink Custom to LinkStack (#3757)

"LittleLink Custom" has been renamed to "LinkStack".

 - Updated domain
 - Updated description
 - Updated demo domain
 - Updated source code URL
 - Updated license

README.md

@@ -1552,7 +1552,7 @@ _Related: [Monitoring](#monitoring), [Bookmarks and Link Sharing](#bookmarks-and
 - [Homer](https://github.com/bastienwirtz/homer) - A dead simple static homepage to expose your server services, with an easy yaml configuration and connectivity check. `Apache-2.0` `HTML5`
 - [Hubleys](https://github.com/knrdl/hubleys-dashboard) - Self-hosted personal dashboards to organize links for multiple users via a central yaml config. `MIT` `Docker`
 - [Jump](https://github.com/daledavies/jump) - Yet another self-hosted startpage for your server designed to be simple, stylish, fast and secure. `MIT` `PHP`
-- [LittleLink Custom](https://littlelink-custom.com/) - Open-source, customizable, self-hosted alternative to services like Linktree and Manylink with an intuitive, easy to use user/admin interface. LittleLink Custom allows you to link all your social media platforms easily accessible on one page. ([Demo](https://demo.littlelink-custom.com/), [Source Code](https://github.com/JulianPrieber/littlelink-custom)) `GPL-3.0` `PHP`
+- [LinkStack](https://linkstack.org/) - Open-source, customizable, self-hosted alternative to services like Linktree and Manylink with an intuitive, easy to use user/admin interface. LinkStack allows you to link all your social media platforms easily accessible on one page. ([Demo](https://linksta.cc/), [Source Code](https://github.com/LinkStackOrg/LinkStack)) `AGPL-3.0` `PHP`
 - [Newtelco Tab](https://github.com/ndom91/newtelco-tab) - Beautiful dashboard and new tab launcher with support for App Shortcuts as well as GDrive, Contacts, and notes. ([Demo](https://portal.newtelco.de/)) `MIT` `Nodejs`
 - [Organizr](https://github.com/causefx/Organizr) - Organizr aims to be your one stop shop for your Servers Frontend. `GPL-3.0` `PHP`
 - [Smashing](https://smashing.github.io/) - Smashing, the spiritual successor to Dashing, is a Sinatra based framework that lets you build excellent dashboards. It looks especially great on TVs. ([Source Code](https://github.com/Smashing/smashing)) `MIT` `Ruby`