Document EnableSendfile.  I'm presuming that directives.html* and
  quick_reference.html* are now autogenerated.  Could someone run the
  xml builder and commit the compiled results?


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@97208 13f79535-47bb-0310-9956-ffa450edef68