Add TMC2130 library to FireStep

[FlyingLotus1983]

Add TMC2130 code to FireStep. This includes:

• [x] Test with Arduino before Smoothie.
• [x] Wrap into a library, if possible.
• [x] Use object-oriented approach so that each driver (x,y,z) is an object
• [x] Add code to initialize, read from, write to, and close the SPI port.
• [x] Add a configuration function that sets up the device for normal use
• [x] Add functions for commonly used registers that might need to be changed often
• [x] Add function to return the back-EMF register value(s)
• [ ] Add statistics for back-EMF sensing (min, max, average, instantaneous)
• [ ] Add functionality to use back-EMF sensing during a homing operation.

[FlyingLotus1983]

TMC2130 library and JSON integration into FireStep is mostly complete. Next is to add hooks into the FireStepDriverWizard for the following parameters.

• [ ] IHOLD
• [ ] IRUN
• [ ] IHOLDDELAY
• [ ] TPOWERDOWN
• [ ] CHOPCONF
  • [ ] toff0
  • [ ] hstrt0
  • [ ] hend0
  • [ ] fd3
  • [ ] disfdcc
  • [ ] rndtf
  • [ ] chm
  • [ ] tbl0
  • [ ] tbl1
  • [ ] vsense
  • [ ] vhighfs
  • [ ] vhighchm
  • [ ] sync
  • [ ] mres
  • [ ] intpol
  • [ ] dedge
  • [ ] diss2g
• [ ] PWMCONF
  • [ ] PWM_AMPL
  • [ ] PWM_GRAD
  • [ ] pwm_freq
  • [ ] pwm_autoscale
  • [ ] pwm_symmetric
  • [ ] freewheel
• [ ] TPWMTHRS
• [ ] THIGH

And also need to read the following parameters:

• [ ] TSTEP
• DRV_STATUS
  • [ ] SG_RESULT
  • [ ] fsactive
  • [ ] CS ACTUAL
  • [ ] stallguard
  • [ ] ot
  • [ ] otpw
  • [ ] s2ga
  • [ ] s2gb
  • [ ] ola
  • [ ] olb
  • [ ] stst
• [ ] PWM_SCALE