This function was only being used from a single place opts/opts.go. This change moves it from a incohesive package (parsers) to the single place it is used. Also made a bunch of the helper methods private because they are not used by any external modules. Signed-off-by: Daniel Nephin <dnephin@docker.com> Upstream-commit: 9b9959105499248ab6cdbfde2277ed1bd83233e3 Component: engine