Add license file

[abroglesc]

Could you please add a license file to this repo? I would like to use this but without a license this is under copyright by default.

When you make a creative work (which includes code), the work is under exclusive copyright by default. Unless you include a license that specifies otherwise, nobody else can copy, distribute, or modify your work without being at risk of take-downs, shake-downs, or litigation. Once the work has other contributors (each a copyright holder), “nobody” starts including you.

Source

I personally would recommend the MIT license.

Adding this would be greatly appreciated!