Evan, Sheila

We made some changes to the LSC model and medm screen as described in ECR 1205.  The main goals were to split the SRCL FF filter into two parrallel banks, so that one can be used for the low frequency feedforward that needs to be tuned as the darm offset is changed and the other can be used for the high frequency part that we don't expect to change much as we change the DARM offset and power up.  I also added a power recycling gain monitor, based on POP A LF divided by IM4 trans sum.  For this we had to add an IPC send to the IMCASC model, an a receive to the LSC top model, in addition to the modifications to the LSC common model.  Both the models and medm screens are checked into svn. Evan also added a PRCL FF path to the FF medm screen, but it is not in the model.

I calibrated the PR gain by looking at a recent lock stretch, taking the average of the normalized arm transmissions and multiplying them by the PRM transmission (2.7%) to get the recycling gain, and then finding the factor needed for the new monitor based on that.