v2.5.0

• added an option to return metadata alongside with interaction results, this metadata is then
  retrievable i.e. during the interactionCheck call. #164, #165
• added an option to return error instead of the standard interaction results, the provider
  will take this error (and error_description when provided) and resolve the authorization request
  with it. #167, #168
• fixed Token#find() swallowing adapter#find errors
• fixed introspection swallowing rethrown adapter#find errors