Project has no licence specified

[matt-senseye]

Thanks for the useful library. During a review of all of the dependencies in our app, we noticed that json-ts does not have a licence specified. Unfortunately due to our policies, this means we might not be able to continue using it unless a licence is added or we are able to gain explicit permission to use the library.

Would it be possible to add licence information to the library to help clarify the conditions of its use?