Calculate measures for block group that ACS does not provide

[andrewxhill]

We should add the Education Attainment variables back to the response, but will need to include those from Tract while the others come from Block.

cc @stuartlynn

[talos]

We actually still have educational attainment at block group level, but there are other columns we lost:

-  not_us_citizen_pop NUMERIC,
-  workers_16_and_over NUMERIC,
-  commuters_by_car_truck_van NUMERIC,
-  commuters_drove_alone NUMERIC,
-  commuters_by_carpool NUMERIC,
-  commuters_by_public_transportation NUMERIC,
-  commuters_by_bus NUMERIC,
-  commuters_by_subway_or_elevated NUMERIC,
-  walked_to_work NUMERIC,
-  worked_at_home NUMERIC,
-  children NUMERIC,
-  population_3_years_over NUMERIC,
-  in_school NUMERIC,
-  in_grades_1_to_4 NUMERIC,
-  in_grades_5_to_8 NUMERIC,
-  in_grades_9_to_12 NUMERIC,
-  in_undergrad_college NUMERIC,
-  speak_only_english_at_home NUMERIC,
-  speak_spanish_at_home NUMERIC,
-  pop_determined_poverty_status NUMERIC,
-  poverty NUMERIC,
-  pop_15_and_over NUMERIC,
-  pop_never_married NUMERIC,
-  pop_now_married NUMERIC,
-  pop_separated NUMERIC,
-  pop_widowed NUMERIC,
-  pop_divorced NUMERIC,

[talos]

FWIW, in individual OBS_GetMeasure calls we now pull the measure from the next-best geometry (if not available at block group, we pull from tract, then county, etc. etc.).