Add libhif.doap
Add libhif.doap

This is also well-known RDF Schema supported by some editors.

Reference: https://github.com/edumbill/doap/wiki
Signed-off-by: Igor Gnatenko <71fb2d16c26f553767b965fdac40e83622cad277@redhat.com>

edynox/libdnf,edynox/libdnf,hughsie/libhif,hughsie/libhif,hughsie/libhif,rpm-software-management/libhif,rpm-software-management/libhif,Conan-Kudo/libhif,edynox/libdnf,Conan-Kudo/libhif,edynox/libdnf,rpm-software-management/libdnf,rpm-software-management/libhif,rpm-software-management/libdnf,Conan-Kudo/libhif,rpm-software-management/libdnf,rpm-software-management/libdnf,hughsie/libhif,rpm-software-management/libhif,Conan-Kudo/libhif