Allow Year outside of 1900-9999 range

[chejennifer]

When running dc-import tool on the dataset/artifacts in https://github.com/bchivers-stanford/psmsl_data_commons_import, get an error that the Year must be between 1900-9999. We should allow for years earlier than 1900

[danbri]

I just ran into this too with @ajaits - some population data that seems to go back to 1408