Color districts using EDR data

[bhrutledge]

Towards #43.

Changes

• Parse EDR Data Google Sheet into JSON
• Join EDR Data with existing legislature data
• Color districts according to legislator grade
• Add legend for district colors

TODO

• I'm not sure about the green color scheme; I think it might make it hard to distinguish the level of support. Do we need 4 grades? Could we use distinct colors for each? That's how the map on https://actonmass.org/the-campaign/ works.

[NONstiky]

Looks good, @bhrutledge!

[mvictor55]

@bhrutledge it looks good to me. I think we may opt to go with the different color approach - but for now I think we can leave it. I'll add it as a question to our beta users.