KitchenAid to Milescraft adapter 8

Updated adapter between a KitchenAid stand mixer attachment hub and a Milescraft 90 degree drill adapter.
There are two sets of changes:
1) To the square piece that fits in the KitchenAid hub. I expanded from 0.45 to 0.47"; this takes the slop out of the fit. (I believe the hub is designed as 12 mm.) I also chamfered the ends of the piece so that it's easier to get it into place.
2) To the cylinder that holds the Milescraft adapter bit. Multiple changes to try to prevent it from eventu