Migrated tests to jest

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

test2/getDaysDiffBetweenDates/getDaysDiffBetweenDates.js

@@ -0,0 +1,3 @@
+const getDaysDiffBetweenDates = (dateInitial, dateFinal) =>
+(dateFinal - dateInitial) / (1000 * 3600 * 24);
+module.exports = getDaysDiffBetweenDates;

test2/getDaysDiffBetweenDates/getDaysDiffBetweenDates.test.js

@@ -0,0 +1,9 @@
+const expect = require('expect');
+const getDaysDiffBetweenDates = require('./getDaysDiffBetweenDates.js');
+
+test('Testing getDaysDiffBetweenDates', () => {
+  //For more information on all the methods supported by tape
+  //Please go to https://github.com/substack/tape
+  expect(typeof getDaysDiffBetweenDates === 'function').toBeTruthy();
+  expect(getDaysDiffBetweenDates(new Date('2017-12-13'), new Date('2017-12-22'))).toBe(9);
+});