Moved utf-8 aware File::Find and Cwd to own module

The utf-8 aware versions of File::Find and Cwd can now be found on CPAN
as File::Find::utf8 and Cwd::utf8 respectively.
Allowing Win32, excluding DOS and OS/2 platforms

It turns out the Win32 platform works just fine (we were guarding this
incorrectly anyway; $^O should have been tested against MSWin32 not
just Win32.
Not decoding @ARGV when perl is run with -CA