Add to mapbox.com/mapbox.js/plugins

[freenerd]

We are keeping track of all our mapbox.js plugins at https://www.mapbox.com/mapbox.js/plugins/ so let's add mapbox-match.js there

• Add to CDN via https://github.com/mapbox/mapbox.js-plugins
• Add link to CDN to Readme here
• Create example documentation like https://www.mapbox.com/mapbox.js/example/v1.0.0/mapbox-directions/
• Make sure mapbox-match.js shows up in https://www.mapbox.com/mapbox.js/plugins/
• Add link to mapbox-match.js to documentation site of the Map Matching API