Vector I/O requests are now processed within a single
set of I/O call batches, rather than each I/O vector
entry (tuple constructed from the types, addrs, sizes
and bufs arrays) being processed individually. This allows I/O to be
more efficiently parallelized among the I/O concentrator processes
during large I/O requests.
* Fixed some calculations and add test cases for issues spotted from review
* Removed a variable that was compensating for previous miscalculations
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