Intermediate kOS Tutorial

No pictures, just text and code. I hope it's not too dry. I haven't tested the code yet either, but it's essentially complete.
Hmm... I think what might make more sense, going forward, is rather than labeling tutorials as purely being easy/intermediate/hard, is to mention what they are going to teach about, and then maybe as a secondary bit of info tag them with a difficulty level, but not use that as the primary descriptor.  This is because once you start expanding past the basics, the topics become more like a tree rather than a flat list.  The topic that one reader needs to know about early on might be a topic that another reader doesn't need to know about until later.  Which one feels more "advanced" might change depending on what the needs of the user are.