Adding Group Metatag

Signed-off-by: evalle <shmarnev@gmail.com>

hack/make/.build-rpm/docker-engine.spec

@@ -2,6 +2,7 @@ Name: docker-engine
 Version: %{_version}
 Release: %{_release}%{?dist}
 Summary: The open-source application container engine
+Group: Tools/Docker
 
 License: ASL 2.0
 Source: %{name}.tar.gz