make dynamic the Oregon average for grassroots funding %

[stochasticTreat]

Right now the "average for grassroots funding" is hard coded at 13%.
This number will vary a lot and it would look funny if someone goes here
http://hackoregonstaging.herokuapp.com/#/oregon
And see's a different number.
Thus, it really should be dynamically generated and not hard coded.
You can get the % by getting the JSON object from this endpoint:
http://54.213.83.132/hackoregon/http/all_oregon_sum/_/
and dividing the "total_grass_roots" field value by the "in" field value.