Fix the -H|-h flag as spotted by Pete in the online doc.

Add the missing -ne in RewriteCond
Add some missing hyperlinks to the corresponding directives.
(r1737767 and r1737769 in trunk)

+ synch with trunk (trailing space removal)

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1737772 13f79535-47bb-0310-9956-ffa450edef68