#100 EventScreen을 GreetingScreen과 EventScreen으로 분리, 세부로직은 EventManager가 담당
#100 EventManager과 RewardManager를 static 클래스로 만듦
#100 [완료] 불필요한 조건문 삭제
Merge pull request #102 from CienProject2014/#100_Detaching_EventScreen's_Feauture

#100 detaching event screen's feauture