Clip states closer to land area based on 2016 districts

[hodgesmr]

This is an extension of #9.

I went ahead and followed the same process but for all 50 states: using @schwanksta's 2016 district geojson to rebuild the state lines much closer to land masses.

If this is not a desirable change, then we can just close both PRs.

[schwanksta]

I think this is a very desirable change in general, though two things: a) the Census actually publishes state shapefiles that are clipped to land (https://www.census.gov/geo/maps-data/data/cbf/cbf_state.html), but b) do we even need states in the repo? I'm not sure of the utility of maintaining our own, but I admit I've never asked anyone.

[ogtega]

Like I said here, additionally, once I resolve a coordinate's district it is really easy to get the coordinate's state. Maybe move the state topology files into their own repo?

[hodgesmr]

@schwanksta a) awesome, thanks for the links! Was digging around for that before I decided to try to generate them, this repo was much easier to find than the census page.

From @ogtega:

Maybe move the state topology files into their own repo?

This seems like a fair idea, given this repo's name. But I also get @schwanksta's question of utility given availability from the Census.