The feCodeGen.pl script was using ./diags.txt and ./diags2.txt to build the...

The feCodeGen.pl script was using ./diags.txt and ./diags2.txt to build the <model>_partConnectionList.txt for each model. This meant that multiple models could not be built at the same time bacause they were sharing the diags files. This commit replaces those file with ones specific to the model being built. We also clean up the code a bit and remove some sleeps that slow down builing the models by 10 s each.