[tlbuild] Graphite support on cygwin

[Ken Brown]

Hi Peter,

This is a very low-priority item, but something I'd like to fix eventually.

Some time ago I mentioned that I had to build xetex without graphite 
support on cygwin because cygwin's gcc didn't (yet) support 
std::wstring.  The latest version of gcc now has that support, so I 
tried again.  The build fails as follows:

../../../libs/graphite/src/font/FileFont.cpp: In member function 'void 
gr::FileFont::initializeFromFace()':
../../../libs/graphite/src/font/FileFont.cpp:211: error: invalid 
conversion from 'gr::utf16*' to 'const wchar_t*'
../../../libs/graphite/src/font/FileFont.cpp:211: error:   initializing 
argument 1 of 'std::basic_string<_CharT, _Traits, _Alloc>& 
std::basic_string<_CharT, _Traits, _Alloc>::assign(const _CharT*) [with 
_CharT = wchar_t, _Traits = std::char_traits<wchar_t>, _Alloc = 
std::allocator<wchar_t>]'

If and when you think it's worth trying to track this down, let me know 
if you need further information.  I'm not going to try to fix it before 
the release of TL2009 unless Karl asks us to rebuild again for some 
other reason.

Thanks.

Ken