[FIX] If a page doesnt have a language it returns null in the inner.GetLanguage 

and that results in a Object Ref in the CachingLanguageGateway, So added an check so it checks if its null and return null cause that's fine. This problem is happening for example when access an languageIntersaction
Merge pull request #550 from EzyWebwerkstaden/master

[FIX] If a page doesnt have a language it returns null in the inner.GetLanguage