Inspired by #3738

This stores a handled Failure with the location where the Rational
was created, and throws that whenever it is being stringified.

    my $a = 0;
    my $b = 1 / $a;
    say "inbetween"
    say $b;

results in:

    Attempt to divide 1 by zero
      in "foo" at $file line 2

    Actually thrown at:
      in "foo" at $file line 4

Passes all tests, but makes handling of Rationals up to 30% slower.