func exploreDirectory (string path) ([]string, error){
    var output []string
    //Get entries
    info, err := ioutil.ReadDir(path)
    if err != nil {
        return nil, err
    }
    for i, _ := range info {
        if !info[i].IsDir() {
            //Output file
            output := append(output, path + "/" + info[i].Name)
        } else {
            //Explore it; it's a directory.
            entries, err := exploreDirectory(path + "/"  + info[i].Name())
            if err != nil {
                return nil, err
            }
            output := append(output, entries...)
        }
    }
    return output, nil
}