Removed the Perl dependencies on Encode, Encode::Locale and Unicode::Normalize.
Added dependency on boost::locale.
Added encode_path, decode_path, normalize_utf8 functions to Slic3r.xs
Slic3r.xs has been made mostly utf8 safe by using the boost::nowide library,
thanks to @alexrj for the idea.
Simplified the encode_path / decode_path stuff:
wxWidgets are unicode already, so there is no need to decode_path() from it.
Perl / win32 interfacing is non-unicode, so decode_path() is executed
on ARGV just at the beginning of the perl scripts.
Removed the deprecated VibrationLimit feature.
Added triangle infill.
The Prusa3D fork of Slic3r has been marked as "Slic3r Prusa Edition"
with menus pointing to the prusa3d/slic3r github release page
and Prusa3D drivers downloads page.
