T1002123 spell checker

I thought this would be a five minute fix but it turned out to be more difficult. At least I could remove my first AspectJ code.
Ok, I was confused. Iulian copied the description from `SpellingService` and not from `SpellingEngine`. I actually didn't implement `ScalaSpellingEngine` it already existed, just at a different location (and I didn't take a look if it can be simplified). I'll give it a look, the `check` method can be simplified too.