Train Sort test

[mauicv]

As an initial test to verify the transformer works i'm training it to sort a sequence of 6 numbers with 3 digits in order of size. It usually gets accuracy ~ 99% on this after less than 10 epochs. I turns out that removing the MLP layer has almost no effect on the result so we should devise a harder test to ensure that we're testing both the MLP and the Attention layer.