Partially empty 2d histogram Plots.jl

[isentropic]

I see,

Plots.histogram2d(beam[:,1], beam[:,2], show_empty=true)

fixes it

Or,
using any of these aliases is also valid

:show_empty_bins, :showemptybins, :showempty, :show_empty, :show_zeros, :showzeros

Hope this would help some users.