Added GMHook

Update README.md

Author: bytecauldron

README.md

@@ -314,6 +314,7 @@ What kind of games can you make in GameMaker? [Check out this list.](https://ste
 - [DHook](https://github.com/tabularelf/DHook) - Discord integration.
 - [GMS2_RPC](https://github.com/Mtax-Development/GMS2_RPC) - Another Discord integration.
 - [NekoPresence](https://marketplace.yoyogames.com/assets/9526/nekopresence) - Oops, all Discord integration.
+- [GMHook](https://github.com/Kruger0/GMHook) - We really like Discord integration.
 - [Steamworks.gml](https://github.com/YAL-GameMaker/steamworks.gml) - Various expansions to Steamworks SDK support in GameMaker: Studio.
 - [Parworks](https://github.com/nkrapivin/Parworks) - Additional functionality for the YYG Steamworks extension.
 - [GOG.gml](https://github.com/GameMakerDiscord/GOG.gml) - A native extension for GOG.com SDK support.