v0.6.1

Changed

• The playground shows the booking date picker: a Book a time shortcut
  on the home screen and a Booking message button, booked in the page.
  The echo test backend answers /booking with the picker too.
• New wiki page, The playground: its panel, and how a link to a setup
  works (the whole setup is in the link; nothing is stored).
• The widget's CSS variables and base styles are minified in the bundle
  like the rest of its CSS: about 0.5 KB less to download.

Fixed

• Widget: a chat opened by the page itself (data-open, such as the
  dashboard's test chat) no longer moves focus into the chat. Focus stays
  where the visitor has it; opening the chat yourself still moves it in.
• Dashboard: Escape closes the account menu even before focus has moved
  into it.