v0.4.0

• Add the reduced-motion option, which sets what the page's
  prefers-reduced-motion media query reports, so pages that honor it skip
  animations and background video.
• SCREENSHOT and SNAPSHOT names may contain hyphens, so
  SCREENSHOT after-verification-code writes after-verification-code.png.
• Lint warns about a count >= 1 assert directly followed by a check on the
  same locator; the second check already waits for the element.