v0.21.9

Added

• Add ICollection::empty()
• Add Arr::of(), Arr::isListOf()

Changed

• Rename:
  • Arr::listOfArrayKey() -> Arr::isListOfArrayKey()
  • Arr::listOfInt() -> Arr::isListOfInt()
  • Arr::listOfString() -> Arr::isListOfString()

Deprecated

• Deprecate Test::isArrayOf() (replaced with Arr::of())

Fixed

• Cli: fix issue where empty default values are displayed in help messages
• Cli: remove escapes from horizontal whitespace to fix issue where help written as Markdown wraps weirdly when rendered