Add MIT License to the project

[jwinpbe]

I don't want to start forking / fixing / working on the code unless I know it's free software. Please consider adding this or apache 2.0, I would rather improve the existing code to work with the new API than make my own library.

If you find software that doesn’t have a license, that generally means you have no permission from the creators of the software to use, modify, or share the software. Although a code host such as GitHub may allow you to view and fork the code, this does not imply that you are permitted to use, modify, or share the software for any purpose.

https://choosealicense.com/no-permission/

Thanks in advance!