dpdk_setup_ports.py: fix add of help in case of "t-rex-64 --help"

dpdk_setup_ports.py: fix add of help in case of "t-rex-64 --help"
dpdk_setup_ports.py: fix warning of TRex is already running if different NICs are being used
singleton_daemon.py: fix error socket in use immediately after check if in use
trex-console: fix crash in case of "tui --help"
trex-console: try-catch commands instead of crashing
add async notification on port status/atttibutes change
add port xstats support
add description of interfaces
main_dpdk.cpp: fix --client_cfg not working with Python API

Signed-off-by: Yaroslav Brustinov <[email protected]>