Merged /httpd/httpd/trunk:r1870020,1874133

Merged /httpd/httpd/trunk:r1870020,1874133

  *) mod_md:
     - Prefer MDContactEmail directive to ServerAdmin for registration. New directive
       thanks to Timothe Litt (@tlhackque).
     - protocol check for pre-configured "tls-alpn-01" challenge has been improved. It will now
       check all matching virtual hosts for protocol support. Thanks to @mkauf.
     - Corrected a check when OCSP stapling was configured for hosts
       where the responsible MDomain is not clear, by Michal Karm Babacek (@Karm).
     - Softening the restrictions where mod_md configuration directives may appear. This should
       allow for use in <If> and <Macro> sections. If all possible variations lead to the configuration
       you wanted in the first place, is another matter.
     [Michael Kaufmann <mail michael-kaufmann.ch>, Timothe Litt (@tlhackque),
      Michal Karm Babacek (@Karm), Stefan Eissing (@icing)]

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1874134 13f79535-47bb-0310-9956-ffa450edef68