Refactor license copy to remove unwrap()

[mstallmo]

Closes #475

I've changed the code that utilized unwrap()and handled the None case of the option explicitly returning an Error if we get a None.

Side note: I also refactored a couple of places in the file based on some clippy linting warnings.

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[ashleygwilliams]

this is a great improvement! thanks so much :)