Wrapping data retrieval and SVI calculation,
find_svi() supports multiple entries of year-state
pairs.
get_census_data() (and find_svi()) uses
zcta-state crosswalks to support state-specific ZCTA-level data
retrieval from 2019-2021. (This functionality is supported by
tidycensus::get_acs() until 2019 as Census Bureau no longer
makes ZCTA shapefiles available by state.)
get_svi() replicates results from CDC/ATSDR SVI
database by matching number of decimals (#12).
More user-friendly CLI error messages in the functions (#3, #4, #7).