code: function(url, callback) {
      console.log("Downloading "+url);
      Espruino.Core.Status.setStatus("Downloading binary...");
      var xhr = new XMLHttpRequest();
      xhr.responseType = "arraybuffer";
      xhr.addEventListener("load", function () {
        if (xhr.status === 200) {
          Espruino.Core.Status.setStatus("Done.");
          var data = xhr.response;
          callback(undefined,data);
        } else
          callback("Error downloading file - HTTP "+xhr.status);
      });
      xhr.addEventListener("error", function () {
        callback("Error downloading file");
      });
      xhr.open("GET", url, true);
      xhr.send(null);
    }
docs: / Gets a URL as a Binary file, returning callback(err, ArrayBuffer)