Merge r1681795, r1682988, r1682979, r1682819, r1682816 from trunk:

Merge r1681795, r1682988, r1682979, r1682819, r1682816 from trunk:

initialize args to not print garbage mem during a RewriteRule parse error

Initialize args to not print garbage mem during a RewriteCond parse error (same as r1681795 for RewriteRule)

Improve style in examples.

Improve error message (related to PR57311 diagnostic)

Concat string at compile time in order to save a few cycles.

Submitted by: covener, jailletc36, jailletc36, jailletc36, jailletc36
Reviewed/backported by: jim

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.4.x@1683113 13f79535-47bb-0310-9956-ffa450edef68