Let's reorganize the stack vignette

[lwasser]

Essentially this vignette is a single overview of stack and crop_image.
It's missing a clean description of stack and how stack works with the parameter options.
It's also missing crop_all.

We should decide whether to have 2 vignettes - or just organize this one to show all three functions:

• crop_image
• crop_all
• stack

https://earthpy.readthedocs.io/en/latest/gallery_vignettes/plot_raster_stack_crop.html