Change connection back to chassis add

It seems that ixConnectToChassis does not work for latest Linux based chassis, while chassis add does work.
If chassis add fails, we try ixConnectToChassis.

Add delay for before reading ixConnectToChassis response

Add delay before reading ixConnectToChassisresponse because otherwise it sometimes fails.

• Fix tests and sample.
• Fix more pre-commit issues.

Change connection to chassis and add port reboot function

• Connect and disconnect with high level commands - ixDis/connectFromChassis
• Support port reset without statistics reset, this with port CPU reboot allows flexibility in port reset option
• Add add_ports command to manage ports without reservation.
• Adjust tests to pytrafficgen 4.0.0
• Fix many pre-commit issues