- Rename WRITE_E_STEP for consistency

- Add BIT and TEST macros
- Add _APPLY_ macros to stepper.cpp to help with consolidation
- Consolidate code in stepper.cpp using macros
- Apply standards in stepper.cpp
- Use >= 0 instead of > -1 as a better semantic
- Replace DUAL_Y_CARRIAGE with Y_DUAL_STEPPER_DRIVERS