Fixes an issue where symlink tests failed on systems that do not support creation of symlinks.
The issue appears on Windows systems due to changed behaviour in File::Find
described
in Perl/perl5#19995.
Symlink tests were previously skipped if symlink()
is not available, and now also if creation of a symlink is not possible.
Fixes #9. Note that on Windows systems, the patch to File::Find
from Perl/perl5#20008 will be required for proper operation.