Update documentation for Performance
Update documentation for Performance

- Apply coding standards
- Reformat Markdown
- Improve wording, fix spelling
- Improve structure
- Delete table of contents inside document

This commit also deprecates the wiki page about performance.

gchtr/timber,jarednova/timber,jarednova/timber,timber/timber,gchtr/timber,gchtr/timber,timber/timber,jarednova/timber