wpkg 0.8.2 available

Testing some more with long filenames there were still quite a few problems to resolve.

Along the way, I found out that the place where --force-configure-any should have been used, I had --force-downgrade instead.

When unpacking packages, the version wasn't being validated as expected.

The Date field would get a time zone of "ric" under MS-Windows. I replaced the output with the expected +XXXX syntax.

As I was updating the tests to fully work under MS-Windows, I had problems with the WPKG_SUBST in a unit test. It actually has to be defined in the main() function to make sure that all tests are working as expected. This solved several problems in the unit tests.

Fixed the filename handling in a tar header. The different length tests were inverted and certain combinations could result in overwritten data. This was part of supporting long filenames although this bug was present in all prior versions (0.7.0 to 0.8.1).

As in a test, the memfile unlink_rf() can fail under MS-Windows if used to remove a directory which was just emptied. We added a second attempt after a small sleep to compensate. This same technique is also used by mingw32 and cygwin implementations, therefore it is no doubt a problem with the MS-Windows implementation of rmdir(). We may later change that function for the equivalent Windows API which may not return too soon.