Test migration to jest by hand

Apparently using regular expressions is way easier.

test/symmetricDifference/symmetricDifference.test.js

@@ -0,0 +1,9 @@
+const expect = require('expect');
+const symmetricDifference = require('./symmetricDifference.js');
+
+
+  test('symmetricDifference is a Function', () => {
+  expect(symmetricDifference).toBeInstanceOf(Function);
+});
+  t.deepEqual(symmetricDifference([1, 2, 3], [1, 2, 4]), [3, 4], "Returns the symmetric difference between two arrays.");
+