v0.9.9

• Bump minimum @vimeo/player version. (@k-p-jones in #191)
• Document controls as pro-account-only. (fd61877)
• Add onPlaying event, fix documentation for onPlay. (@Aliath in #212)
• Add playbackRate prop. (@chidimi in #220)
• Support changing the quality prop during playback. (941b68b)
• Add support for passing a URL to the video prop, eg. for embedding private videos. (e7128b6)