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/common/base_classes/FOCDriver.h

@@ -1,7 +1,8 @@
-#ifndef FOCMOTOR_H
-#define FOTMOTOR_H
+#ifndef FOCDRIVER_H
+#define FOCDRIVER_H
 
 #include "Arduino.h"
+#include "../foc_utils.h"
 
 class FOCDriver{
     public: 
@@ -11,6 +12,9 @@ class FOCDriver{
 
         virtual void disable() = 0;
 
+        virtual void setPwm(float a, float b, float c);
+        // virtual void setPwm(uint8_t a, uint8_t b);
+
         long pwm_frequency;
         float voltage_power_supply;
         float voltage_limit;
@@ -18,4 +22,4 @@ class FOCDriver{
         void* params = 0;
 };
 
-#endif
+#endif