emit and accept modern query string parameter delimiters (;).

Thus column headers no longer contain unescaped ampersands.

PR: 10880
Reviewed by: Will Rowe, Jeff Trawick


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/APACHE_2_0_BRANCH@99519 13f79535-47bb-0310-9956-ffa450edef68