The behavior was changed with #6317 so that regardless of spelling in
the shader, the include path will conform to the host OS style for the
purposes of the include handler. This just adds a release note for that
new behavior.
Fixes#6669
Moving the source file for the README.md for github and nuget releases
into the DXC repo. It should be updated with relevant notes for the
upcoming release whenever they are made in main such that they will
already be available when the release is built.
Part of #6697