Create separate balancing areas for Hawaii's islands

[grgmiller]

In the EIA data, only a single official balancing authority is associated with Hawaii. However, according to this 2016 report from the Hawaii state energy office, "Each of Hawaii’s six main islands has its own electrical grid, not connected to any other island."

This suggests that we could create de facto BAs for each of the six main islands if we could identify the location of each plant based on its coordinates, which should be pretty straightforward.