setup: set env $GIT_WORK_TREE when work tree is set, like $GIT_DIR
[git] / contrib / credential /
drwxr-xr-x   ..
drwxr-xr-x - gnome-keyring
drwxr-xr-x - netrc
drwxr-xr-x - osxkeychain
drwxr-xr-x - wincred