* docs(guide): clean up canvas particle sim code examples
* Use ES6 syntax
* Format code for easy readability
* Normalize single vs. double quotes
* Adjust spacing
* Add link to inverse-square law wikipedia page for additional information
* docs(guide): use arrow functions in particle sim examples
* docs(guide): minor edits to animation-in-canvas
* Use ES6 syntax in code examples
* Clean up formatting in code examples for clarity
* Remove unnecessary sentence for brevity
* docs(guide): use arrow functions for canvas animation examples
