I\'ve created a VSPackage which should copy some XML schema files to Visual Studio\'s installation path: %VS install path% \\Xml\\Schemas.
Your package will not be able to copy files to the VS installation path because admin rights are required for that and VS doesn't run elevated (with admin rights) by default, and a package should not force VS to run elevated. The setup of your package could do that, but not your package.
That said, see:
HOWTO: Get information about the Visual Studio IDE from a Visual Studio package.