v0.16.2

Fixed

• Sign out took about 25 seconds in Chrome: the Clear-Site-Data: "cache"
  header it sent makes Chrome clear the whole cache before it moves on. The
  header is gone; instead a page is served private, no-cache, so it is
  checked with the Worker every time it is shown and none read before signing
  out is shown from the cache afterwards. Markdown, images and search data keep
  their minute.
• The Content Security Policy blocked a font the build inlines as data:,
  and a PDF's page, which shows the file in an <object>. It now allows
  font-src 'self' data: and object-src 'self'.