A wrapper over AWS.S3 library which is compatible with Node.Js's fs module
##Usage
var fs = require('s3-fs');
fs.configure({
//S3.config.update arguments
});
fs.exist('/bucketname/directory1/file.ext', function(exist){
});
// or
fs.exist('bucketname/directory1/file.ext', callback );
// The leading '/' is optional.
fs.exist
fs.readFile
fs.writeFile
fs.readdir