Works for me in superficial manual testing, but needs automated tests.
Also currently does two server round trips (one for planting locations
and one for sunninesses); it would be better to combine these into one,
or alternatively to create a "crop stats" API endpoint and calculate
sunniness stats in SQL.
on both crops and places pages
Did this because the clusters were annoyingly over-general, eg. showing
164 people in the eastern part of North America. Cluster radius of 20px
is about the radius of the cluster icon itself. Seems to work better
eg. for separating Melbourne from Sydney on the world map.