User Guide for Tree Structures

[aaronzedwick]

Closes #804

Overview

Adds a user guide for the tree structures, BallTree and KDTree.

PR Checklist

General

• [x] An issue is linked created and linked
• [x] Add appropriate labels
• [x] Filled out Overview and Expected Usage (if applicable) sections

Examples

• [x] Any new notebook examples added to docs/examples/ folder
• [x] Clear the output of all cells before committing
• [x] New notebook files added to docs/examples.rst toctree
• [x] New notebook files added to new entry in docs/gallery.yml with appropriate thumbnail photo in docs/_static/thumbnails/

[review-notebook-app[bot]]

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[rajeeja]

@philipc2 how about icons for users guide notebooks?

[aaronzedwick]

@philipc2 how about icons for users guide notebooks?

I asked him about that, he said he doesn't think we need them for the user guides.