Switched one test over to XCTestExpectation to prevent failure
Removed ATH test helper from CoreDataConcurrencyTest
Removed AsyncTestHelper from BlogJetpackTest (and header file)
Fixed remaining unit tests
Removed the AsyncTestHelper in favor of XCTestExpectation
Sort order on test folder updated
Merge pull request #2200 from wordpress-mobile/issue/1613-test-expectations

Replace AsyncTestHelper with XCTestExpectation