Add "how to make sure things are working" page to docs?

[billbrod]

Add a page that describes how to make sure things are working: visualize the overall loss, sure, but also the model-specific loss plot and make sure the loss is going down in each component. Thus, describe how to create said plots (or link to documentation elsewhere). Add advice for what to do to make things better, from both model-development and fixed-model perspectives. Things like playing with optimization, normalization, etc.