TravisCI: Run NodeJS 4
TravisCI: Run NodeJS 4

cvazac/resourcetiming-compression.js,LouisMagarshack/resourcetiming-compression.js,cvazac/resourcetiming-compression.js,nicjansma/resourcetiming-compression.js,nicjansma/resourcetiming-compression.js,LouisMagarshack/resourcetiming-compression.js