Log Message:
2.0.3:
* Address missing OIDC errors and fix a typo in the AccountSelectionRequired \ 
exception.
* Update proxy keys on CaseInsensitiveDict.update().
* Redirect errors according to OIDC's response_mode.
* Added universal wheel support.
* Added log statements to except clauses.
* According to RC7009 Section 2.1, a client should include authentication \ 
credentials when revoking its tokens.
  As discussed in 339, this is not make sense for public clients.
  However, in that case, the public client should still be checked that is \ 
infact a public client (authenticate_client_id).
* Improved prompt parameter validation.
* Added two error codes from RFC 6750.
* Hybrid response types are now be fragment-encoded.
* Added Python 3.6 to Travis CI testing and trove classifiers.
* Fixed BytesWarning issued when using a string placeholder for bytes object.
* Documented PyJWT dependency and improved logging and exception messages.
* Documentation improvements and fixes.