Cavern Stairs (openforge 2.0 compatible)

Hi Folks!

I created a Staircase, that you can use in combination with my elevated tiles (https://www.thingiverse.com/thing:3523328) if you prever those over ladders. The Staircase is quite small to fit as a 2x2 tile, but at least one mini should be able to stand on the middle level. As the rest of the things I remixed and designed, those are made to fit on any 2x2 openforge 2.0 bases. Keep in mind that you'll need to mirror the stairs in your slicer software, if you want the left oriented ve