rather than creating small 1024 byte buckets of output data,

rather than creating small 1024 byte buckets of output data,
create a transient bucket pointing directly to the BIO mem buff.
this makes for a dramatic increase in performance. previously,
downloading large files (2Mb-5Mb-ish) made my laptop start to
smoke from the fan spinning so fast to cool the cpu.
also, apache stylize churn_output()
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git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@90497 13f79535-47bb-0310-9956-ffa450edef68