Request to update licence.
It is not clear if the software is licensed by either MIT or Happy Bunny or BOTH by MIT and Happy Bunny.
In the official website ( https://glm.g-truc.net/0.9.9/index.html ) I notice "OR":
"The source code and the documentation, including this manual, are licensed under the Happy Bunny License (Modified MIT) or the MIT License."
Also, there is "OR" in the readme.md ( https://github.com/g-truc/glm )
"The source code and the documentation are licensed under both the Happy Bunny License (Modified MIT) or the MIT License."