v3.6.4

Added:

• New conda smithy ci-skeleton subcommand that generates conda-forge.yml
  and recipe/meta.yaml files for using conda-forge / conda-smithy as
  the CI configuration outside of configuration. Calling rerender after
  ci-skeleton will generate the configuration files. This is a great way to
  either bootstrap CI for a repo or continue to keep CI up-to-date.
  The recipe/meta.yaml that is generated is just a stub, and will need to
  be filled out for CI to properly build and test.

Fixed:

• Fix an issue with empty host
• Fix python lint for recipes with outputs