fix #1456 don't allow a corrupted user file to prevent access to simulation data. Reset to empty if read fails.
fix #1456 don't allow a corrupted user file to prevent access to simulation data. Reset to empty if read fails.

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