Update SPIP source code URL and license (#2508)

README.md

@@ -555,7 +555,7 @@ _CMS are a practical way to setup a website with many features. CMS often come w
 - [Redaxscript](https://redaxscript.com) - Ultra lightweight CMS for MySQL, SQLite and PostgreSQL. ([Demo](https://demo.redaxscript.com/login), [Source Code](https://github.com/redaxmedia/redaxscript)) `GPL-3.0` `PHP`
 - [Roadiz](https://www.roadiz.io/) -  Modern CMS based on a node system which can handle many types of services. ([Source Code](https://github.com/roadiz/roadiz)) `MIT` `PHP`
 - [SilverStripe](https://www.silverstripe.org) - Easy to use CMS with powerful MVC framework underlying. ([Demo](http://demo.silverstripe.org/), [Source Code](https://github.com/silverstripe)) `BSD-3-Clause` `PHP`
-- [SPIP](http://www.spip.net/fr) - Publication system for the Internet aimed at collaborative work, multilingual environments, and simplicity of use for web authors. ([Source Code](https://core.spip.net/projects/spip/repository)) `GPL-2.0` `PHP`
+- [SPIP](http://www.spip.net/fr) - Publication system for the Internet aimed at collaborative work, multilingual environments, and simplicity of use for web authors. ([Source Code](https://git.spip.net/)) `GPL-3.0` `PHP`
 - [Squidex](http://squidex.io) - Headless CMS, based on MongoDB, CQRS and Event Sourcing. ([Demo](http://cloud.squidex.io), [Source Code](https://github.com/Squidex/squidex)) `MIT` `.NET`
 - [Strapi](https://strapi.io/) - The most advanced open-source Content Management Framework (headless-CMS) to build powerful API with no effort. ([Source Code](https://github.com/strapi/strapi)) `MIT` `Nodejs`
 - [Subrion](http://www.subrion.org) - Subrion is a free open source content management system that allows you to build websites for any purpose. Yes, from blog to corporate mega portal. ([Demo](http://demos.subrion.com), [Source Code](https://github.com/intelliants/subrion)) `GPL-3.0` `PHP`