more robust repository links
more robust repository links

improve Markdown formatting and add clickable links to GitHub profiles of the maintainers of each repository

joecridge/p5.js,processing/p5.js,mlarghydracept/p5.js,mlarghydracept/p5.js,joecridge/p5.js,dhowe/p5.js,limzykenneth/p5.js,dhowe/p5.js,bomoko/p5.js,processing/p5.js,limzykenneth/p5.js,bomoko/p5.js