fix docs on regex matching, change the actual ordering of arguments to match...

fix docs on regex matching, change the actual ordering of arguments to match the docs, and enforce AP_MAX_REG_MATCH in the function, should it somehow return more matches than we have allocated

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1467557 13f79535-47bb-0310-9956-ffa450edef68