Add 'client/util/client-dmg/' from commit '97e26ba2a077ab46408a85092a92a5f4cc7b5073'

git-subtree-dir: client/util/client-dmg
git-subtree-mainline: 97e26ba2a077ab46408a85092a92a5f4cc7b5073
git-subtree-split: 97e26ba2a077ab46408a85092a92a5f4cc7b5073
experimenting with client-dmg git subtree