Rewrite printf/write with Unicode::GCString/Unicode::LineBreak

[doherty]

From http://stackoverflow.com/questions/6162484/why-does-modern-perl-avoid-utf-8-by-default/#6163129:

Perl built-ins like printf and write do the wrong thing with Unicode data. You need to use the Unicode::GCString module for the former, and both that and also the Unicode::LineBreak module as well for the latter.