Stackable Vertical Laptop Stand

This is part of a chain of remixes. The [original model](https://www.thingiverse.com/thing:3463871) is a simple yet elegant laptop holder. That model was later [modified](https://www.thingiverse.com/thing:4912496) to be printed horizontally, which results in a much stronger model.

This model makes the laptop holder stackable, so that several laptops can be placed next to each other while the holders connect to each other, providing stability.