[Checkins] [zopefoundation/zope.interface] 75facc: Make @implementer and classImplements not re-decla...

[Jason Madden]

  Branch: refs/heads/issue199
  Home:   https://github.com/zopefoundation/zope.interface
  Commit: 75facc3f3f45674bd06fba680535c76d68fb45ff
      https://github.com/zopefoundation/zope.interface/commit/75facc3f3f45674bd06fba680535c76d68fb45ff
  Author: Jason Madden <jamadden at gmail.com>
  Date:   2020-04-06 (Mon, 06 Apr 2020)

  Changed paths:
    M CHANGES.rst
    M docs/api/declarations.rst
    M src/zope/interface/declarations.py
    M src/zope/interface/tests/test_declarations.py

  Log Message:
  -----------
  Make @implementer and classImplements not re-declare redundant interfaces.

classImplementsOnly and @implementer_only can still be used to do that.