Replace License

[davidbannon]

The "clear-bsd license" appears to be loosing traction, hard to find, becoming obscure. https://choosealicense.com/licenses/bsd-3-clause-clear/

Replace with the MIT one ? https://choosealicense.com/licenses/mit/ - appears far more recognisable and still says what we need. Still need to list all the existing, "other" licenses.

Davo