Refresh issue when switching to having a sizeColumn defined in a layer

[astrofrog]

This is different from #192 because I really can't get the layer to refresh even when changing e.g. the color and even if I don't update the data. If I define a layer with:

csv = 'a,b,c\r\n1,10,20\r\n5,11,20\r\n10,11,21\r\n2,10,21\r\n'
layer = wwtlib.LayerManager.createSpreadsheetLayer('Sky', 'My Layer', csv)
wwt.gotoRaDecZoom(150, 20, 90)
layer.set_lngColumn(1)
layer.set_latColumn(2)
layer.set_sizeColumn(-1)

(so no sizeColumn initially) then later define the sizeColumn with:

layer.set_sizeColumn(0)

the layer doesn't update to reflect the new and varying point sizes