Nodejs Express with mongodb toturials

1. simple api with mongodb
2. request static img file
3. using simple template engine with handlebar

> test urls

GET http://localhost:3030/articles -> get article list

POST http://localhost:3030/articles -> create article

GET http://localhost:3030/articles/:num -> get article

PUT http://localhost:3030/articles/:num -> update article

DELETE http://localhost:3030/articles/:num -> delete article

GET http://localhost:3030 -> handlebar web page

GET http://localhost:3030/static/img/node.png -> get static img