Migrate to 1.0 badges

[stenington]

Badgetest should issue 1.0 badges by default, with 0.5.0 and signed badges as options as well.

[stenington]

This implies some API changes to the underlying server. I think the new API should look something like:

Paths:

• /v0.5.0
  • /raw.json: unhashed email old-style badge
  • /hashed.json: hashed email old-style badge
  • /error.json: maybe get rid of this?
• /v1.0.0
  • /hosted.json: hashed/unhashed email can be specified in the new assertion structure
  • /signed.json: signed 1.0-style badge
• /echo.json
  • returns empty JSON object, unless query params used
  • email query param makes no sense though
• Query params:
  • email: email address to issue to
  • override: url-escaped JSON object with override values for assertion object
  • x.y: attribute to overwrite
  • the 1.0 assertion spec breaks down into multiple json files linked by urls. For the purposes of overwriting, treat it as one big object with the url replaced by the object itself.