Taint tests disabled in DBI-1.31

[Bradley Baetz]

Tim,

The tests for the new Taint stuff which was added appear to be disabled
in 1.31 - line 227 has

if (0 && is_tainted($^X) && !$DBI::PurePerl) {

Was there a reason for this? Thats not in the final pach which I sent,
and the tests pass for me.

Thanks,

Bradley