Merge pull request #1677 from and-semakin/master

Add Teeworlds

README.md

@@ -757,6 +757,7 @@ _Command-line file upload_
 - [Posio](https://github.com/abrenaut/posio) - Geography multiplayer game. ([Demo](https://posio.abrenaut.com/)) `MIT` `Python`
 - [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`
 - [Spyfall](https://github.com/mpcovcd/spyfall) - Fan made web version of the Spyfall party game. ([Demo](http://spyfall.crabhat.com/)) `MIT` `HTML/Javascript`
+- [Teeworlds](https://www.teeworlds.com) - Open source 2D retro multiplayer shooter. ([Source Code](https://github.com/teeworlds/teeworlds)) `BSD-3-Clause/Other` `C++`
 - [TournamentMango](http://tournamentmango.com/) - TournamentMango is an open source tournament bracket and user management system. You can build an archive of players and keep track of all their scores over time as well as their regular characters, games, and aliases. ([Source Code](https://github.com/seiyria/tournamentmango)) `MIT` `Javascript`
 
 ## Gateways