Please copy tools/win32-loader/unstable to .../testing

["Adam D. Barratt" <adam@adam-barratt.org.uk>]

Hi,

As discussed with OdyX, please copy the current version of
tools/win32-loader from unstable/ to testing/.

We'll then unblock the source package, so that we can get it migrated
before the 8.1 point release (which includes a version of win32-loader
that's newer than the current version in testing).

Thanks,

Adam