v1.0.9

The primary change is clearer behavior for nested unions. See the new nested subcommands example.

What's Changed

• Nested union support, apply prefix_name flag to subcommands by @brentyi in #436
• Fix minor edge cases in counter args, helptext, attrs's Factory(takes_self=True) by @brentyi in #437
• Fix negative number edge case for nargs consumption by @brentyi in #438

Full Changelog: v1.0.7...v1.0.9