OAuth: Fix APIv1Controller's handling of missing tokens
OAuth: Allow use of captchas

Add support for "scopeless" oauth 2 endpoints,
set captcha endpoints to be scopeless.
/dev/api: Fix docs for /api/v1/me/prefs
Refactor "allowed_scopes" -> "required_scopes"

This makes it more clear what the parameter does.
/dev/api: Reorder decorators so 'view code' points to the right place
trophy: Add trophy listing api.
karma: Add karma list api endpoint.
Update promo slideshare url.