ensure that data comes back in utf-8, on MSWin32

e.g.
https://github.com/msysgit/msysgit/wiki/Git-for-Windows-Unicode-Support

http://www.cpantesters.org/cpan/report/0c934f2a-6c17-1014-a945-92c1c8f412ad
http://www.cpantesters.org/cpan/report/0c8fa937-6bf4-1014-9444-f87fab4d9e9f
fix header levels