Address ref creation

[kai-fukutaki]

• Adds address reference table creation code
• Cleans up column names
• Improves geocoding of Medicaid
• Adds geo_hash_clean for merging to geocode table
• Adds geocode_success column to say which addresses successfully geocoded (useful for iterating on geocode process and for users to subset addresses if desired)

[alastairmatheson]

Good updates, with a few more noted in my email.