LU-9474 tests: rewrite copytool_setup to use stack_trap

LU-9474 tests: rewrite copytool_setup to use stack_trap

Replace copytool_setup with its rewrite (copytool setup) as much
as possible. There are some interaction between copytool_setup()
and other test functions (mainly import_file() and its derivatives).
Later patch(es) will handle those interactions and completely
remove copytool_setup() from sanity-hsm.

Among the benefits of using the new copytool() function:
 - it has a nice command line interface
 - it uses stack_trap() to register clean up actions
 - it makes it easier to run sanity-hsm with other copytools

Test-Parameters: trivial clientcount=3 mdscount=2 testlist=sanity-hsm,sanity-hsm
Change-Id: I81635da39f19d001e0f5c6348b233b45c4298fd0
Signed-off-by: Quentin Bouget <quentin.bouget@cea.fr>
Reviewed-on: https://review.whamcloud.com/30097
Tested-by: Jenkins
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Henri Doreau <henri.doreau@cea.fr>
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>