The other ipynb is just used to generate the council boundaries, this will be used to analyze them.
Reading shapefile into rtree index now
Reading districts into rtree, then testing for intersection against everything in washington census file.  This take a long time, maybe should save a subset of the WA census to speed it up.  Looking at population properties, what else can I get per-tract info on?
Getting outer boundary of Seattle from union of districts, had to inflate the boundary a little to make it work- so the outer boundary isn't good for finding intersections with fine resolution- instead stick to per-district intersections.