D:P: Convert to use modern Test functions

D:P: Convert to use modern Test functions

This commit copies much of test.pl from blead to replace the Test ones.

These versions are much friendlier to use.  Several .t files required
minor changes to work with these.  pv_tools.t was the only file using
the old obsolete skip() functionality fully.  The new version does not
do a 'last SKIP', for compatibility.

like and unlike were not ported because of the absence of qr// in perls
this is supposed to work on.

And the portions of test.pl that were copied also required a few minor
changes to work back to 5.3.7.

Not all the ported functionality is currently in used.  It may be that
changes will have to be made to it to get it to work; or will have to be
deleted.