Update FIPS codes to 2019 version

[cdmgtri]

https://www.census.gov/programs-surveys/geography/geographies/reference-files.html

• From the US Census Bureau home page, go to "Browse by topic" / "Geography" / "Geographies" / "Reference Files", or use the link above
• Work backwards from the current year and go to the most recent fips codes ("2019 FIPS Codes")
• Download both spreadsheets to get the state and the county codes
• Remove "00" region and division codes from the state-geocodes list
• Filter on Summary Level "050" for county codes from the all-geocodes list