doc/astf minor update
doc/astf minor update

Signed-off-by: Hanoh Haim <1f34741bfa88280155d5053f5e8f4b89d8aa79bf@cisco.com>

dimagol/trex-core,dimagol/trex-core,kisel/trex-core,dimagol/trex-core,dimagol/trex-core,kisel/trex-core,kisel/trex-core,dimagol/trex-core,kisel/trex-core,kisel/trex-core,kisel/trex-core,dimagol/trex-core