Change to more permissive MIT license

[emirkmo]

https://choosealicense.com/licenses/mit/#

Changing to MIT license would allow this to be used by people like Microsoft, who cannot use GPL licenses since it would force them to open source their code.

While I choose GPL when I can, it would be nice if this was in PowerToys..

(see microsoft/PowerToys#6434 (comment))

[jm33-m0]

Makes sense, I just asked if they want to use my script, will change license if necessary