[PATCH] BTT patch: (2/3) per-IO stream output

[PATCH] BTT patch: (2/3) per-IO stream output

Two major updates:

(1) Added in some robustness - can accept out-of-order traces, and can
"orphan" unfinished IO streams.

(2) Added in ability to put IO streams to a file, sending Q-to-C traces
on a per-IO bases.

The additional robustness comes at some expense (performance), and
so I will look into that next. (Perhaps see what those Judy trees buy
us... :-) )

Signed-off-by: Alan D. Brunelle <Alan.Brunelle@hp.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>