make strict check work again

If not applying the fix, the improved tests would fail.

Fixes #34.
I'm still struggling with the naming and meaning of those variables.
What exactly does the strict mode mean? Will it turn a valid address with warnings into an invalid address if enabled?
What does `$dns` mean? That the DNS check (if it has been performed at all) found a valid entry?
How do DNS check and strict mode correlate? Are they meant to independently make validation fail, or is the DNS check just adding more warnings which would make validation fail only with strict mode enabled?

I think more comments and renaming some of the variables would help in making the code easier to understand. But that can be done separately.