Release 0.13.1.dev0

templates: login: Use /login/ as endpoint

Needed because otherwise the POST-ed data will be sent to a
redirect from /login to /login/, triggering an unnecessary
browser warning.

CHANGES: Prepare 0.13.0.beta0

Prepare release 0.12.6.1 - hotfix release

Fix compatibility with werkzeug 2.1+

Prepare release 0.12.6.1 - hotfix release

setup.py: Pin werkzeug<2.1

`utils/hash.py` uses `pbkdf2_bin` from werkzeug, which will
be removed in 2.1.
Pin the version until a fix is made.

See error:
```
isso/utils/hash.py:71: DeprecationWarning: 'pbkdf2_bin' is deprecated and will be removed in Werkzeug 2.1. Use 'hashlib.pbkdf2_hmac()' instead.
    return pbkdf2(val, self.salt, self.iterations, self.dklen, self.func)
```

setup.py: Note compatibility with python 3.10

Release 0.12.5

Import upstream version 0.12.4, md5 2d70f2e2f9899a6e5fd4100f1bde268d

Release 0.12.4.