v0.0.2: Improvements and Fixes

This release contains assorted improvements and fixes, including:

• Better docs (the never ending struggle)
• Stamping support in docker_bundle and docker_push
• A few new contrib features: passwd and docker_build with tagging helpers.
• Fix the top-level rules are broken issue (again). Now with testing!
• Workaround an argparse bug that broke '--' in entrypoint and cmd.
• Remove support for Docker <1.10 (beginning of some broader cleanup)
• Performance improvements via google/containerregistry

A lot of the changes in this release were in support of (shameless plug) distroless.