Simple-Stack 2.2.1

Simple Stack 2.2.1 (2020-01-12)

• FIX: The explicit parent scope chain was not always resolved correctly if a key is only a ScopeKey.Child, but not a ScopeKey, and the key did not register any new scopes (as all scopes defined by the ScopeKey.Child had already been registered by previous keys).

This could provide incorrect results in findScopesForKey(key, EXPLICIT), and could skip a HandlesBack service in the current top key's explicit parent chain.