Added Minetest to the Games section

README.md

@@ -785,6 +785,7 @@ _Games, game servers and control panels._
 - [elevatorsaga](http://play.elevatorsaga.com/) - The elevator programming game. ([Source Code](https://github.com/magwo/elevatorsaga)) `MIT` `Javascript`
 - [Hextris](https://github.com/Hextris/hextris) - Fast paced HTML5 puzzle game inspired by Tetris. ([Demo](https://hextris.github.io/hextris)) `GPL-3.0` `HTML5`
 - [Lila](https://lichess.org/) - The forever free, adless and open source chess server powering lichess.org, with official iOS and Android client apps. ([Source Code](https://github.com/ornicar/lila)) `AGPL-3.0` `Scala`
+- [Minetest](https://www.minetest.net/) - An open source voxel game engine. Play one of our many games, mod a game to your liking, make your own game, or play on a multiplayer server. ([Source Code](https://github.com/minetest/minetest)) `GPL-2.1/CC BY-SA 3.0/Other` `C++`
 - [Posio](https://github.com/abrenaut/posio) - Geography multiplayer game. `MIT` `Python`
 - [RconCli](https://github.com/gorcon/rcon-cli) - CLI for executing queries on a remote Valve Source dedicated server using the RCON Protocol. `MIT` `Go`
 - [SourceBans++](https://sbpp.github.io) - Admin, ban, and communication management system for games running on the Source engine. ([Source Code](https://github.com/sbpp/sourcebans-pp)) `CC-BY-SA-4.0` `PHP`