Release für Contao 5

[BugBuster1701]

Anpassungen nötig.

• [x] postLogin hook
  • The postLogin hook has been removed. Use the LoginSuccessEvent instead.
• [x] postAuthenticate hook
  • The postAuthenticate hook has been removed. Use the security.authentication.success (AuthenticationSuccessEvent) instead.
• [x] postLogout hook
  • The postLogout hook has been removed. Use the LogoutEvent instead.

Events in Docs grob erläutert: https://docs.contao.org/dev/reference/events/