* Use better regex for IPv6 to allow a lot more valid IPv6 addresses

* Adding some unit tests for is_absolute_uri in uri_validate

* Make unit tests Python 3.6 compatible

* Remove redundant import after unit test simplification for py36

* update Changelog

* Remove redundant coding line

Like with the implicit grant, we need to override add_id_token to pass
the nonce from the current request to GrantBase.add_id_token in order
for the ID token to have the correct nonce.

Add test that the nonce is in ID token from hybrid OIDC flow.

Fixes: #746

* Adding support for RSA-SHA256.

* Added support for HMAC-SHA512, RSA-SHA256 and RSA-SHA512 signature methods.

* Made version dependencies consistent.

* Updated OAuth1 signature tests.

* Fixed parsing of netloc/host. Deprecated old functions.

* Refactored and expanded tests to include signature validate.

* Update docs for HMAC-SHA512, RSA-SHA256 and RSA-SHA512 signature methods.

* Updated code comments in oauth1 signatures module.

* Updated changelog.

* Update docs/feature_matrix.rst

Co-Authored-By: Omer Katz <omer.drow@gmail.com>

* Used parenthesis instead of backslash to break lines.

* Fixed typo

Co-authored-by: Omer Katz <omer.drow@gmail.com>

Co-authored-by: Omer Katz <omer.drow@gmail.com>

Replace the use of external 'mock' package with built-in Python
unittest.mock (present since py3.3).  This also fixes all test failures
for me.