Code cleanup and new dependencies 

Hi Please pool my changes:
First three patches are cleanups for core client's code
Lats for patches are update for libaio dep and new dependencies e2fsprogs, xfsprogs, fio.
It is reasonable to have fio in dep/library because it is generic tool which required by many
tests like xfstests,  various performance tests and fio itself.
I've bunch of fixes for tests which wants to use this dependencies which I'll publish soon