Some visual and bug fixes
* Fixed the floating artifacts, as those were what the code in RenderBlockExtender were actually drawing
 + I was making this more complicated than it should be; since BlockExtender returns 0 as its render type, it will already use standard drawing, so it's totally unneeded in RendererBlockExtender.
* Fixed the face of the mini block extender inside wireless block extenders not being drawn
 + Revert "Fixed undisguised block extenders having an invisible face (might be a better way to do this because there are some seaming issues with this method)"

This reverts commit bb7c3023f9d3dc6d8689c6073766ea42e2065897.