Move API-based formatting logic to wikibase.RepoApi.FormatValueCaller

Change-Id: I9800efbc4303d35da46ed97ee6722301b46ff552
Introduce ValueViewBuilder

Change-Id: I8bb89d007cc5ea048767da026848f9db246a9c42
Merge "Move API-based formatting logic to wikibase.RepoApi.FormatValueCaller"
Merge "Introduce ValueViewBuilder"