Thanks to Hilko Bengen for characterizing the issue and
providing an initial version of this patch.

Thanks to Hilko Bengen for spotting the problem.

When you import a string value like:
  "Foo"="Bar"
using Windows regedit program, implicit nul-termination is added
to the value (not the key), so what is stored in the value would
be something like:
  hex(1):42,00,61,00,72,00,00,00
where two of the trailing zero bytes come from the implicit
terminator.  This corrects the reg_import function so it works
the same way.

Although these modules are optionally used by the Perl tests,
they aren't necessary and won't break the build if they are not
there.  These modules aren't available in RHEL 5.  Therefore
remove these checks.