* Website and documentation refresh: move pages to mjambon.com/atdgen,
  fix broken links pointing to the defunct oss.wink.com, create single
  sub-site for everything atdgen-related (biniou, yojson, atd, atdgen,
  atdgen-omake, atdgen-make, documentation)

* JSON object syntax for variants, e.g.:
  type t = A | B of int
  Currently supported: "A"
                       ["B", 123]
                       <"A">
                       <"B":123>
  To do: {"A": null}
         {"B": 123}

* Do not encode variants with the non-standard angle bracket syntax by default

* Support 32-bit floats in Biniou, for more compact storage
