update license for twiki

- http://svn.twiki.org/svn/twiki/trunk/core/LICENSE

README.md

@@ -2065,7 +2065,7 @@ _See also: [Wikimatrix](https://www.wikimatrix.org/), [Wiki Engines - WikiIndex]
 - [Raneto](https://raneto.com/) - Raneto is an open source Knowledgebase platform that uses static Markdown files to power your Knowledgebase. ([Source Code](https://github.com/ryanlelek/Raneto)) `MIT` `Nodejs`
 - [TiddlyWiki](https://tiddlywiki.com/) - Reusable non-linear personal web notebook. ([Source Code](https://github.com/Jermolene/TiddlyWiki5)) `BSD-3-Clause` `Nodejs`
 - [Tiki](https://tiki.org/HomePage) - Wiki CMS Groupware with the most built-in features. ([Demo](https://tiki.org/Try-Tiki), [Source Code](https://sourceforge.net/p/tikiwiki/code/HEAD/tree/)) `LGPL-2.1` `PHP`
-- [TWiki](https://twiki.org/) - TWiki is a Perl-based structured wiki application, typically used to run a collaboration platform, knowledge or document management system, a knowledge base, or team portal. ([Demo](https://twiki.org/cgi-bin/view/Sandbox/WebHome), [Source Code](http://svn.twiki.org/svn/twiki/)) `GPL-1.0` `Perl`
+- [TWiki](https://twiki.org/) - TWiki is a Perl-based structured wiki application, typically used to run a collaboration platform, knowledge or document management system, a knowledge base, or team portal. ([Demo](https://twiki.org/cgi-bin/view/Sandbox/WebHome), [Source Code](http://svn.twiki.org/svn/twiki/)) `GPL-2.0` `Perl`
 - [WackoWiki](https://wackowiki.org/) - WackoWiki is a light and easy to install multilingual Wiki-engine. ([Source Code](https://github.com/WackoWiki/wackowiki)) `BSD-3-Clause` `PHP`
 - [Wiki.js](https://js.wiki/) - Modern, lightweight and powerful wiki app using Git and Markdown. ([Demo](https://docs.requarks.io), [Source Code](https://github.com/Requarks/wiki)) `AGPL-3.0` `Nodejs`
 - [wiki](https://git.mills.io/prologic/wiki) - Simple Markdown based wiki engine. ([Demo](https://wiki.mills.io)) `MIT` `Go`