Create proximity.json

Added the Proximity API
Added support table for domcontentloaded event
validate-jsons.js can now run from every cwd without throwing.
Removed incorrect links from DOMContentLoaded.json
Merge pull request #554 from AurelioDeRosa/patch-1

Create proximity.json
Merge pull request #555 from branneman/master

Added support for DOMContentLoaded
data update
data update
data update