Make perchild work with the new bucket_allocation API. Also, allow

the Perchild directives to take both numerical UID/GID and the
logical user name/group name.
PR:	9784
Submitted by:	named UID/GID logic: Scott Lamb <slamb@slamb.org>


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@94352 13f79535-47bb-0310-9956-ffa450edef68