v0.9.0

• Remove internal calls to Dict
• Store the type of the token in the typ field rather than the aud field
  The aud field should default to the sub or failing that, the iss.
  This is to facilitate implementing an OAuth provider or just allowing
  folks to declare their own audience.

v0.8.1

Fix a bug with logout where it was not checking the session, only the assigns This meant that if you had not verified the session the token would not be revoked.