graphene: adding display range for cell 2d dataset
graphene: axisrange can now choose suggested display range
colormap: making sure optimized color map can still work outside optimized range
statistics: adding lazy statistics object
axisRange: moving the state of the aggregation in the axisRangeInstance.
The main reason is performance: we want to access the range of the data only if required, so that it doesn't have to be calculated if there is no need.
intensity graph: making sure lazy statistics is not inadvertently calculated.