Save to ______ 
Save a stream to a file.
API
var saveTo = require('save-to')
var stream = fs.createReadStream('some file.txt')
saveTo(stream, 'destination.txt', function (err, destination) {
if (err) throw err
})
saveTo(stream [, destination] [, options], callback)
stream is the source stream, for example a request.
destination is the path where the stream will be saved.
callback(err, destination)
The options are:
destination - if you don't specify destination as an argument.
length - expected byte length. Throws an error if it does not match the stream's length.
limit - maximum byte length. Throws an error if the stream is larger than this size.