Adds module.setupOnce and module.teardownOnce to QUnit

QUnit.module('Example', {
  setupOnce: function () {
    // runs once before anything else in the module
  },
  setup: function () {
    // runs before each unit test
  },
  teardown: function () {
    // runs after EACH unit test in this module
  },
  teardownOnce: function () {
    // runs once after all unit tests finished (including teardown)
  }
});