[Checkins] [zopefoundation/z3c.jbot] 84ddc9: fix travis, add cache

[Jens W. Klein]

  Branch: refs/heads/fix-8
  Home:   https://github.com/zopefoundation/z3c.jbot
  Commit: 84ddc9a3a160f5bec826b1d2e3303d89472da2e6
      https://github.com/zopefoundation/z3c.jbot/commit/84ddc9a3a160f5bec826b1d2e3303d89472da2e6
  Author: Jens W. Klein <jk at kleinundpartner.at>
  Date:   2020-08-10 (Mon, 10 Aug 2020)

  Changed paths:
    M .travis.yml

  Log Message:
  -----------
  fix travis, add cache