Add more capacitors to impedance setup SVG
Add configurable device load test voltage...

 - Allow user to specify voltage to use during calibration
   of device load measurement circuit.
 - Only calibrate against device load test capacitors that
   that will not exceed the current limit (~10mA RMS) of
   the feedback [op-amp][1] at the requested test voltage.

[1]: http://ww1.microchip.com/downloads/en/DeviceDoc/21685d.pdf