copies the ansible-core command and shell modules, but adds a new option: modifies.

modifies is gramatically similar to creates and removes but the logic underneath is different. While creates and removes give the task a chance to exit early, modifies allows the task to define whether or not it changed based on the contents of a list of files, and it allows the task to produce a diff.

modifies:
  type: list
  elements: str
  description:
    - A list of file paths. A tempfile copy is made of each file before command execution,
    - and then `results['changed']` `results['diff']` are set by comparing after command execution.