Plot Top Losses

[basedrhys]

Is your feature request related to a problem? Please describe.
One helpful model debugging tool is to plot the instances which our model gave highest loss for -- where our predictions were most different to ground truth. This provides some useful feedback on edge cases / areas our data may be faulty.

Describe the solution you'd like
A similar functionality in WDL4J, initially for image models but potentially all models trained in WEKA

Additional context
Notebook