first layer square test print | bed leveling

There are two sizes for 18x18 printbeds and 22x22 printbeds (I'll prob add a 25x25 version in the future)The lines of the squares are 0.6mm wide, so if you have a bigger line width set in your slicer it will probably throw an error (something like “empty first layer”). Maybe I'll make a version with wider lines in the future.