Add Grist to Office Suites (#2853)

README.md

@@ -1328,6 +1328,7 @@ _Related: [Wikis](#wikis)_
 - [CryptPad](https://cryptpad.fr/) - CryptPad is the zero knowledge realtime collaborative editor (rich-text, files, source-code, ...). ([Source Code](https://github.com/xwiki-labs/cryptpad)) `AGPL-3.0` `Nodejs`
 - [EtherCalc](https://ethercalc.net/) - Web spreadsheet. ([Source Code](https://github.com/audreyt/ethercalc)) `CPAL-1.0/Other` `Nodejs`
 - [Etherpad](https://etherpad.org/) - Etherpad is a highly customizable Open Source online editor providing collaborative editing in really real-time. ([Demo](https://demo.sandstorm.io/appdemo/h37dm17aa89yrd8zuqpdn36p6zntumtv08fjpu8a8zrte7q1cn60), [Source Code](https://github.com/ether/etherpad-lite)) `Apache-2.0` `Nodejs`
+- [Grist](https://getgrist.com/) - Grist is a next-generation spreadsheet with relational structure, formula-based access control, and a portable, self-contained format. Alternative to Airtable. ([Demo](https://docs.getgrist.com), [Source Code](https://github.com/gristlabs/grist-core)) `Apache-2.0` `Nodejs/Python`
 - [Infinoted](https://github.com/gobby/gobby/wiki/Dedicated%20Server) - Server for [Gobby](https://github.com/gobby/gobby/wiki), a multi-platform collaborative text editor. ([Source Code](https://github.com/gobby/gobby)) `MIT` `C++`
 - [ONLYOFFICE](https://helpcenter.onlyoffice.com/faq/server-opensource.aspx) - Office suite that enables you to manage documents, projects, team and customer relations in one place. ([Source Code](https://github.com/ONLYOFFICE/DocumentServer)) `AGPL-3.0` `Nodejs`
 - [PHPOffice](https://github.com/PHPOffice) - PHPOffice contains libraries which permits to write and read files from most office suites. `LGPL-3.0` `PHP`