Change references to BLDCDriver to FOCDriver in current sense base class

change setPwm function in FOCDriver to accept 3 args, with a default value for the 3rd

Change stepper driver classes to use 3 arg setPwm, ignoring 3rd arg.

created InlineCurrentSenseSync class in lib/currentsense.

fixed timer bug in calibrate encoder, in main

defined a label for serialusb, to make it easier to swap out.

firmware/lib/Arduino-FOC/src/drivers/StepperDriver2PWM.cpp

@@ -86,7 +86,7 @@ int StepperDriver2PWM::init() {
 
 
 // Set voltage to the pwm pin
-void StepperDriver2PWM::setPwm(float Ua, float Ub) {
+void StepperDriver2PWM::setPwm(float Ua, float Ub, float Uc) {
   float duty_cycle1(0.0f),duty_cycle2(0.0f);
   // limit the voltage in driver
   Ua = _constrain(Ua, -voltage_limit, voltage_limit);
@@ -104,4 +104,4 @@ void StepperDriver2PWM::setPwm(float Ua, float Ub) {
 
   // write to hardware
   _writeDutyCycle2PWM(duty_cycle1, duty_cycle2, params);
-}
+}