Standardized IoCU Rm resistors for Iabc of AFE,INV

Previous design for 1kVA per rack had different Rm resistors in the ADC
signal conditioning circuits for AFE and INV in order to best utilize the
measurable range of the ADC. This allowed a higher current possible to be
measured by the AFE channels.

Higher current needs and the desire to standardize some of the signal
conditioning gains, circuits, etc. led to a change today in the IoCU Rm
resistors for racks 1 and 2 AFE/INV. The Analog Input Mapping.xlsx was
also updated to the Sharepoint site.

Now all ADC channels on the IoCU board have Rm = 357||357 = 178.5 ohm
except for channels B7,A5,A7 which have Rm open to measure vabc references
from RTDS, respectively.

This modifies the iabc current measurement scaling in the DSP code. See
accompanying Powerpoint slides for the NLDL tutorial series for notes on
how these scale factors are calculated. Some comments in the code have
been updated to reflect this change as well.

R1 on the voltage transducer boards are also standardized across the AFE
and INV now with 24.75 kohm for va,vb,vc measurements and 39 kohm for the
one DC voltage measurement on the AFE.

Some old comments in the code were also removed.
First commit in ONRdemo branch.

This branch is meant to quickly bring the racks to a state where
all 4 DSPs can be programmed from the same CCS project. This means
having NPC code (PWMs disabled right now) to send the DAC values to
dSPACE as well as individual PWM enables for AFE and INV separated
for racks 1 and 2. This can be seen by the additional #ifdef npc
and #ifdef b2b.
Changed INV to closed loop references.

This commit was part of some documentation steps to show
others how to go through cloning a repo, checking out a
branch, making edits, making a commit, then pushing
changes to Github.
Added separate CAN address for rack 2 PWM enables.

Added a second pair of CAN addresses for rack 2 AFE and INV PWM enables.

Testing today consisted of testing each rack from AFE-INV(openloop)-NPC(diodes)
up to 5kW with NHR 9200 load. This followed by AFE-INV(closedloop)-NPC(diodes)
individually to the load. After connecting the NPC outputs together, the load
was apply first slowly up to 5kW then a 0-5kW step change. Then 5-8kW followed
by a 0-8kW step change. Final increase up to 10kW then 0-10kW. A previous
modification had rack 1 NPC input inductors at 0.6mH and rack 2 at 2.07mH
which caused an imperfect power balance.

The rack 1 inductors were changed back to the original 2.07mH set and 0-10kW
test was redone showing better power balance. However, even with closed loop
inverter control the output of the two NPCs in diode-rectifier mode had
a significant voltage drop under load.
Changed NPC DAC outputs to have Iabc
Merging ONRdemo