Fix typo as spotted by Wolfgang in online doc (r1750439 in trunk)

Be more consistent in <highlight> block layout in XML.
No visual change (r1750441 in trunk)

Synch with trunk (mainly <highlight> block layout)
Do not use " around parameters in syntax

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1750444 13f79535-47bb-0310-9956-ffa450edef68