This is similar to network scopes where a volume can either be `local` or `global`. A `global` volume is one that exists across the entire cluster where as a `local` volume exists on a single engine. Signed-off-by: Brian Goff <cpuguy83@gmail.com> Upstream-commit: 2f40b1b281a3be8f34d82a5170988ee46ea1f442 Component: engine