[Python-checkins] [python/cpython] bd82a0: Update Travis Doc build config (GH-1565)

[GitHub]

  Branch: refs/heads/2.7
  Home:   https://github.com/python/cpython
  Commit: bd82a070cdebaede9b5287ba5285cf3e79f34dd3
      https://github.com/python/cpython/commit/bd82a070cdebaede9b5287ba5285cf3e79f34dd3
  Author: Zachary Ware <zachary.ware at gmail.com>
  Date:   2017-05-13 (Sat, 13 May 2017)

  Changed paths:
    M .travis.yml

  Log Message:
  -----------
  Update Travis Doc build config (GH-1565)

Build the 'suspicious' doc target, turn on warnings-as-errors on the
docs, and always build the docs.  This better matches master's doc build
setup.