Migrated tests to jest

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

test6/sortedIndex/sortedIndex.test.js

@@ -0,0 +1,10 @@
+const expect = require('expect');
+const sortedIndex = require('./sortedIndex.js');
+
+test('Testing sortedIndex', () => {
+  //For more information on all the methods supported by tape
+  //Please go to https://github.com/substack/tape
+  expect(typeof sortedIndex === 'function').toBeTruthy();
+  expect(sortedIndex([5, 3, 2, 1], 4)).toBe(1);
+  expect(sortedIndex([30, 50], 40)).toBe(1);
+});