Migrated tests to jest

Used jest-codemods to migrate, will have to pass everything by hand before we can merge.

test3/isArray/isArray.test.js

@@ -0,0 +1,10 @@
+const expect = require('expect');
+const isArray = require('./isArray.js');
+
+test('Testing isArray', () => {
+  //For more information on all the methods supported by tape
+  //Please go to https://github.com/substack/tape
+  expect(typeof isArray === 'function').toBeTruthy();
+  expect(isArray([1])).toBe(true);
+  expect(isArray('array')).toBe(false);
+});