various bugfixes and improvements

comIF/OBSW_Ethernet_ComIF.py

config/OBSW_Config.py

gui/OBSW_TmtcGUI.py

obsw_tmtc_client.py

sendreceive/OBSW_MultipleCommandsSenderReceiver.py

sendreceive/OBSW_SequentialSenderReceiver.py

sendreceive/obsw_command_sender_receiver.py

sendreceive/obsw_single_command_sender_receiver.py

sendreceive/obsw_tm_listener.py

tc/OBSW_TcPacker.py

tc/OBSW_TcPacket.py

tc/OBSW_TcService2.py

tc/OBSW_TcService200.py

test/OBSW_PusServiceTest.py

test/OBSW_UnitTest.py

tm/OBSW_PusTm.py

tm/OBSW_TmPacket.py

utility/OBSW_ArgParser.py

utility/obsw_tmtc_printer.py