[Checkins] [zopefoundation/Zope] 49decb: Alert box: added chevron icon for expanding box

[drfho]

  Branch: refs/heads/issue_29
  Home:   https://github.com/zopefoundation/Zope
  Commit: 49decbf08746c5a6f0d3bf6b5f81342de582e7f0
      https://github.com/zopefoundation/Zope/commit/49decbf08746c5a6f0d3bf6b5f81342de582e7f0
  Author: Dr. Frank Hoffmann <Dr. Frank Hoffmann at HAL01>
  Date:   2019-05-03 (Fri, 03 May 2019)

  Changed paths:
    M src/zmi/styles/resources/zmi_base.css
    M src/zmi/styles/resources/zmi_base.js

  Log Message:
  -----------
  Alert box: added chevron icon for expanding box