Headphone Stand - Vertical print

Modified the headphone stand for vertical printing without supports.

Also modified to better fit the build area of the Cetus3D Extended. Width reduced to 82% (feet spread), 3% boost to length and 15% boost to height.

**NOTE: Latest version looks like it slices really nicely at .2mm layer height/200 micron. Will print at lower resolutions but might have some roughness on the bottom of the center bridge**

Removing the Work in Progress tag but can address issues if they pop up.