Write SOP for Power Supply (Keithley 228A)

[tylerhull]

Page exists, needs SOP.

https://github.com/psu-epl/psu-epl.github.com/tree/96871d31e86f171ea7600604522907436b551909/doc/equip/testing/ETL/keithley228A

[jejor]

i've uploaded the pdfs containing hella info on this equipment. I started the SOP but will be on the east coast for the rest of the summer. if someone else wants to run through operation i've uploaded hella references to help out.