Update docs

[bw4sz]

No description provided.

[bw4sz]

I did a doc run with the aim of

1. Covering updates to code that are outdate, like visualize.plot_results() or any return_plot=True
2. Reducing any text that gives a 'tree' first or only feel to the package.
3. Added a prediction page to the 'user guide' that covers the pieces that are in 'getting started', closes The predict page is harder to see in the docs. #863, and related to Batch Predicitions #856

[henrykironde]

Still need some changes in the comparison.rst I am reviewing it

[henrykironde]

@bw4sz, this section contains duplicate content and feels a bit lengthy. I've tried condensing it into a shorter version—could you take a look and see if we can find a balance between the original and the shorter version? Of course, this is subjective, so feel free to share your thoughts.