[Checkins] [zopefoundation/Zope] 6e567f: Fix file content type check, refs #123.

[GitHub]

  Branch: refs/heads/py3-merge
  Home:   https://github.com/zopefoundation/Zope
  Commit: 6e567f2164494c4e388fefb96a0d2b1de5cdefaa
      https://github.com/zopefoundation/Zope/commit/6e567f2164494c4e388fefb96a0d2b1de5cdefaa
  Author: Hanno Schlichting <hanno at hannosch.eu>
  Date:   2017-05-13 (Sat, 13 May 2017)

  Changed paths:
    M src/OFS/Image.py

  Log Message:
  -----------
  Fix file content type check, refs #123.