v5.4.0

update Node.js to v5.4.0 (close #20)

v5.2.0

update Node.js to v5.2.0 (close #16)

v5.1.0

update README for Node.js 5.1.0

v4.2.2

update README for Node.js v4 "Argon"

v5.0.0

update Node.js to v5.0.0 (close #7)