Espresso Tamper (50mm)

A remix of the **@alga42's** design of a 58mm Espresso Tamper. This is a 50mm version, with a few changes to it and its holder as well.

I made the grip a bit oblong. not visually noticeable but IMHO it fits nicer into a human hand when it's slightly oval. Result feels good.

Changed the tamper end to 50mm, so it fits into a Salton-brand (not-so–fancy-but-serviceable) espresso maker. (EX-96)

Made the base a bit thicker.

I've removed a big chunk of material from the interior of the