Merge branch 'chunked-iolog-reading' of https://github.com/aclamk/fio

* 'chunked-iolog-reading' of https://github.com/aclamk/fio:
  iolog: Added new option description to HOWTO
  iolog: Added option read_iolog_chunked. Used to avoid reading large iologs at once. 	Allows iologs to be infinite, generated.

diff --cc HOWTO
Simple merge

diff --cc backend.c
Simple merge

diff --cc fio.1
Simple merge

diff --cc fio.h
Simple merge

diff --cc iolog.c
Simple merge

diff --cc options.c
Simple merge

diff --cc thread_options.h
Simple merge