Caliper and Ruler holder

This is a remix of the Gridfinity caliper holder.

I printed the original and found my calipers were a fairly tight fit, especially my ones at work. I opened up the hole for the calipers so it is easier to get in and out and I keep a steel ruler and no memory cards at so changed that around to hold my ruler, there is still one place for an SD card. I also removed the gridfinity base.