Add ability to name the landuse.timeseries and other output files in subset_data

subset_data has the --out-surface to explicitly name the surface dataset. There should also be an option to name the output landuse.timeseries file. And the testing extended to cover the creation of landuse.timeseries files. This also should be done for the mesh file, datm, and domain files.

Or perhaps a better way, would be to have the user enter something like "file description suffix"? This would be the identifier for the files, and the different ones would use the same suffix, with assumed prefixes for the different file types.