to create a package that refers to a license that is not a system
license or contained in the package
* added package-info flags (currently only approve_license and
system_package)
* adjusted package-reader/writer and pkgman accordingly
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@40393 a95241bf-73f2-0310-859d-f6bbb57e9c96
