[cipd] Deprecate -list in favor of -ensure-file.
[cipd] Deprecate -list in favor of -ensure-file.

R=vadimsh@chromium.org
BUG=663843

Review-Url: https://codereview.chromium.org/2651563005

luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go,luci/luci-go