small changes for singlescript mode, errormodel

config/jet.py

dartwrf/__init__.py

dartwrf/assimilate.py

dartwrf/obs/error_models.py

dartwrf/prepare_wrfrundir.py

dartwrf/print_config.py

dartwrf/utils.py

dartwrf/workflows.py

multiple_exps.py

templates/namelist.input

test-singlenode.py

timer.py