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## Description
Refreshed Hub Quickstart.
- Added a brief intro.
- Added the "how to find an image" use-case.
- Updated pull/push steps to use the same image to show how easy it is
to extend images.
- Moved install DD and create an account as prereqs to keeps the steps
Hub-focused.
- Updated next steps to have a more natural flow related to the previous
step.
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Signed-off-by: Craig <craig.osterhout@docker.com>
Sarah Sanders
Craig Osterhout
David Karlsson