MINOR: Refactor code layout now that a "new" kind of model exists: `tinho`

[tallamjr]

Now we have essentially 3 models, atx, t2 and tiny t2 aka tinho, it is getting hard to get abreast of which models/architectures achieve what.

Perhaps by moving tinho model and code into it's own directory, this might make life a bit easier, 🤷🏻‍♂️ maybe

This should only be a short sprint (max 1hr) to try out and see...