plot evolution of HSAs through the iterations

[aghaynes]

Is your feature request related to a problem? Please describe.
No related to a problem.
Might be nice to have a way to plot how a HSA evolves through iterations.

Describe the solution you'd like

hsa_evol(hsa_object, "HSALabel")

Describe alternatives you've considered

ramp <- colorRampPalette(c("darkred", "red", "orange", "yellow", "green", "blue", "darkblue"))(14)
graphics.off()
minimap(shp, polygon = "BE", zoomout = .000000001, lab = FALSE, bcol = "black", lakes = lakes, col = "white")
mapply(function(x, y){
  plot(shp[rownames(shp@data) %in% hsa$lookups[[x]]$MedStat[hsa$lookups[[x]]$assignment == reg], ], col = y, add = TRUE)
}, x = 14:1, y = ramp)