Changes to existing files:
ReaderWriter.cpp -- to support writeNode() of course.
ReaderWriterATTR.cpp -- to support writeObject -- we write .attr files for textures, if they don't already exist.
AttrData.cpp/.h -- Minor fixes.
CMakeLists.txt -- to include the new files in the build."
From Robert Osfield, port to non Windows platforms just required fixing of header capitilization errors
that windows lets through the net due to having a case insensitive file system.
