"compile-time refinement only works with literals" for NonNegBigDecimal when a Double literal is used

Hi!

I'm trying to make a `NonNegBigDecimal` at compile-time. The `auto._` import didn't work, so I tried it by hand:

```scala
NonNegBigDecimal(1.01)
```

but I get `"compile-time refinement only works with literals"`. I understand this might be because Scala has no literals for `BigDecimal`, but a case like this should probably be allowed.