10V test over 732B-4 of new A3, 3458B@NPLC100, AVG512

Vertical span +/-0.275ppm from 10VDC to match 0.55ppm transfer stability spec.

Result CSV-data from HP 3458A

Workflow:

* RPI accesses DMMs via GPIB and reads data.
* Data is formatted by python script into DSV string and written/append to file on FTP
* DSV-file is visible publicly on https://xdevs.com/datashort/
* Page http://xdevs.com/datalog_mm/ runs D3.js javascript library to read DSV file test.log to input data
* D3.js plots SVG graph online :)