Version 0.8.2

Enhancement

• new function as.HTML for bsdoc objects. It return the raw HTML of
  a bsdoc document. (suggested by Tyler Beason)
• function raphael.html now returns a list with javascript instructions,
  HTML code and id values.

Debug

• fix an encoding issue in pptx with bullets (reported by Jonathan
  Oxborrow)
• fix an issue with NA values in FlexTable (reported by Vadim
  Bondarenko)
• the package is now configured so that headless mode is always true.