[Chiara, Jim, Jenne]

We added senders and receivers to the seiproc model so that we will also eventually be able to do CPS_DIFF stuff between the test masses, which we hope will help with earthquake and windy times.  (The ETM ISIs needed restarting anyway, to pull in a bug fix that the vertex ISIs got some time ago).  We also added receivers and switcher matrices, so that we can do the PRCL, MICH, and SRCL offloading either using the sus M1 outputs or the calibrated LSC signals. This required restarting the PRM, BS, SRM sus models. 

Also, I've updated and tested the SEI_DIFF guardian, and it reliably can turn on and off the CPS portions of the SEI DIFF system (which are the only parts we're using so far without one of us watching). 

I wrote a small script to do an on/off test that hopefully someone can run tonight - it'll run for 6 hours, but is fine for someone to ctrl-c out of if needed.

>> python /ligo/home/jenne.driggers/LHO_work/2019_10_28_ISI_MC2_DIFF_TF/Change_SEI_DIFF_guardian.py