Added missing calls to setUp & teardown in tests

http://book.cakephp.org/2.0/en/development/testing.html#test-case-lifecycle-callbacks

>setUp is called before every test method. Should be used to create the objects that are going to be tested, and initialize any data for the test. Always remember to call parent::setUp()

> tearDown is called after every test method. Should be used to cleanup after the test is complete. Always remember to call parent::tearDown().