Fix for shape-component sometimes erroring. see: https://github.com/donmccurdy/aframe-physics-system/pull/94 and https://github.com/donmccurdy/aframe-physics-system/pull/95

use latest dists for aframe-physics-system and aframe-physics-extras (fixes #269). Fix issue where phyiscal hand attached to cursor-controller wasn't being set properly and also add back hoverable component to ducks.

and disconenct cleanup regression