Add node modules and new code for release (#57)

Co-authored-by: taakleton <taakleton@users.noreply.github.com>

node_modules/underscore/modules/isNaN.js

@@ -0,0 +1,7 @@
+import { _isNaN } from './_setup.js';
+import isNumber from './isNumber.js';
+
+// Is the given value `NaN`?
+export default function isNaN(obj) {
+  return isNumber(obj) && _isNaN(obj);
+}