Scope.specify(...): ResolverAdapter.specifyAValueForResolver

- renamed (Relaxed)ResolverNoInstanceCreation.resolving_null(_optionally) to resolving_null_for_a_definition(_optionally)
- used in (Relaxed)ResolverNoInstanceCreation.resolving_null(_optionally)
- fixed typo in ResolverAdapter.specifyImplementationForResolver()