`setHref` is unsafe

[nsaunders]

The issue is demonstrated here. Check the console to find the error. Providing an absolute URL to setHref seems to be the only way to avoid an error.

Regardless, the type of setHref should be String -> URL -> Maybe URL or similar, in order to convey the notion of failure.

[mjepronk]

OK, good catch. I agree the type should be refactored to return Maybe URL. PR welcome :-)

Are there any use cases for setHref? If not, I'm also fine dropping this function from the API.