RxSwift Input Output

Reference

• https://coding-idiot.tistory.com/7
• https://andy-archive.tistory.com/149
• https://s2ung.tistory.com/35
• https://velog.io/@melt/iOS-Fitapat-MVVM-클린-아키텍처-RxSwift-Presentation-Layer-도입기
• https://nsios.tistory.com/71
• https://green1229.tistory.com/549
  = https://babbab2.tistory.com/185