Accessible map template requires legend to be shown

[nwisehart]

Expected Behavior:
Legend should be active and displayed on map open.

Context:
For users with visual impairments, a legend provides a meaningful way to navigate data outside of using the map. Also when legend information is ordered or sorted by the data it is portraying (ex. regions ordered by population density), it provides clearer context to the significance of the data and the relationship between data points.

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See original at: kellyhutchins/a11y-map#18