Removed check for `last_itime` when determining whether a NetCDF file is a legal restart file.  The `last_itime` variable only exists in RSF files with Lynch-Stieglitz model.
Removed check for `last_itime` when determining whether a NetCDF file is a legal restart file.  The `last_itime` variable only exists in RSF files with Lynch-Stieglitz model.

citibeth/modele-control,citibeth/modele-control,citibeth/modele-control,citibeth/ectl,citibeth/ectl