adding sample data directory and first version of synthetic data file

CSV format sample synthetic dataset:
Household ID, Last, First, Middle, YoB, MoB, DoB, Address, City, State, Zip

Optional 'Household ID' field created to distinguish households generated by the US Census logic of synthetic households vs naively grouping 'person' entities by addresses: in this case there are significantly fewer addresses chosen to randomly assign to household groups.

Later we can keep identical household groupings and randomly assign addresses from a larger pool.