In dashboard dependency tree, strike out non-selected dependencies

E.g. for https://storage.googleapis.com/cloud-opensource-java-dashboard/dashboard/target/dashboard/io.grpc_grpc-auth_1.15.0.html , for Guava, both 20.0 and 19.0 appear, and it looks like 20.0 is the selected version. It would be nice to have 19.0 and its dependencies stricken out so it is easier to see the chosen versions.