[Checkins] [zopefoundation/zope.proxy] 1c3670: Restore installation of the proxy.h header.

[Jason Madden]

  Branch: refs/heads/deprecated-setuptools-features
  Home:   https://github.com/zopefoundation/zope.proxy
  Commit: 1c3670350243fd643ef45543489f801790c43940
      https://github.com/zopefoundation/zope.proxy/commit/1c3670350243fd643ef45543489f801790c43940
  Author: Jason Madden <jamadden at gmail.com>
  Date:   2020-01-20 (Mon, 20 Jan 2020)

  Changed paths:
    M setup.py

  Log Message:
  -----------
  Restore installation of the proxy.h header.