Reduce the manualarity of managing bucket brigade lists by using the

new AP_RING macros. Most of this commit is fairly pedestrian as you
would expect, but I had to redo the chunking filter because of the
amount of pointer juggling it did. I have done some minimal testing
of this patch and it seems to work.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@86178 13f79535-47bb-0310-9956-ffa450edef68