[Checkins] [zopefoundation/persistent] d1966b: No longer use shut down API.

[GitHub]

  Branch: refs/heads/master
  Home:   https://github.com/zopefoundation/persistent
  Commit: d1966b534e92add92847c25de9b03ccfadd3ceae
      https://github.com/zopefoundation/persistent/commit/d1966b534e92add92847c25de9b03ccfadd3ceae
  Author: Michael Howitz <mh at gocept.com>
  Date:   2018-02-21 (Wed, 21 Feb 2018)

  Changed paths:
    M .travis.yml

  Log Message:
  -----------
  No longer use shut down API.