port allure spock adapter from mbryzhko/allure-spock-extension

following events are fired:
beforeSpec - TestSuiteStartedEvent
  beforeFeature - TestCaseStartedEvent
  afterFeature - TestCaseFinishedEvent
afterSpec - TestSuiteFinishedEvent

following events are fired for data-driven test:
beforeSpec - TestSuiteStartedEvent
  beforeIteration - TestCaseStartedEvent
  afterIteration - TestCaseFinishedEvent
afterSpec - TestSuiteFinishedEvent