[Checkins] [zopefoundation/zope.password] 21b78c: Add a KDF password manager.

[GitHub]

  Branch: refs/heads/issue9
  Home:   https://github.com/zopefoundation/zope.password
  Commit: 21b78c44f2519f8b95a1a48ea7901fb8e89bb163
      https://github.com/zopefoundation/zope.password/commit/21b78c44f2519f8b95a1a48ea7901fb8e89bb163
  Author: Jason Madden <jamadden at gmail.com>
  Date:   2017-08-24 (Thu, 24 Aug 2017)

  Changed paths:
    M CHANGES.rst
    M docs/narrative.rst
    M src/zope/password/configure.zcml
    M src/zope/password/password.py
    M src/zope/password/testing.py
    M src/zope/password/tests/test_password.py

  Log Message:
  -----------
  Add a KDF password manager.

Fixes #9

Also refactor some of the internals of password.py to remove
accumulated duplication in match() methods and encoding.