Makie plot of a two dimensional DimArray should use the right aspect automatically

[felixcremer]

When I plot a Raster and then change the window size I can end up with a very stretched version of the plot I can fix this by calling ax.aspect = DataAspect() which gives the image below.

I think it would be good to automatically fix the Aspect of the plot, but I am not sure, whether DataAspect is the right call or whether we could derive a proper aspect ratio from the data or the dimension information.

[rafaqz]

Im also not sure what makes sense as a default here

[rafaqz]

Can we set this default in Rasters.j but not Makie.jl?

(I wish we could defined Attributes in convert_arguments...)