Multi-function test cube

I wanted a simple and quick to print but still useful test to fine-tune a multitude of parameters, so i made this. This is not a test to test the limits for your printer, but rather finding a "good enough".

These are some of the things i can test with it:
- Dimensions: The basic cube is 20mm, the holes are 10mm and the well on top is 16x16mm on the inside with 2mm thick walls.
- Layer adhesion: Use pliers to break the upper wall off or put the pliers in the round hole trying to pry the bloc