Adds some VirtualBar settings to TXpid

this adds those settings to TxPID:

Roll VbarSensitivity, Pitch VbarSensitivity, Yaw VbarSensitivity,Roll Vbar.Kp, Roll Vbar.Ki,
Roll Vbar.Kd, Pitch Vbar.Kp, Pitch Vbar.Ki,Pitch Vbar.Kd, Yaw Vbar.Kp, Yaw Vbar.Ki, Yaw Vbar.Kd

It's untested in flight, but setting part in GCS is ok.