made refreshSimulationData() private, whenModelsLoaded() sets up callback even if already loaded, guard against missing simulationStatus model in persistentSimulation
made refreshSimulationData() private, whenModelsLoaded() sets up callback even if already loaded, guard against missing simulationStatus model in persistentSimulation

radiasoft/sirepo,mrakitin/sirepo,radiasoft/sirepo,mkeilman/sirepo,mkeilman/sirepo,mrakitin/sirepo,mkeilman/sirepo,mrakitin/sirepo,radiasoft/sirepo,radiasoft/sirepo,radiasoft/sirepo,mrakitin/sirepo,mkeilman/sirepo