Expression: Manually adjust color range

[davidarndt]

From feedback Apr 10, 2019: "I am using your tool to plot heatmaps of gene expression data. In my case, there are some outliers or extreme values that I do not want to arbitrarly remove. These extreme values cause that the color range visualization is not useful because most of data points are shown with white color (in the blue-yellow color representation). What is really needed is the option for the user to set the color range values manually and not only automatically by row or column adjustment. I am using column adjustment right now and obtaining a range from blue to yellow equivalent to: -10 to +2. However, most of the data have values between -2 and +2. Therefore, in my case, to obtain a useful representation I would need to manually set that color spectrum should be considered between -2 and +2 only."