Revert "Add 3d Viewer xBlock"
Revert "Add 3d Viewer xBlock"

Stanford-Online/edx-platform,Stanford-Online/edx-platform,caesar2164/edx-platform,Stanford-Online/edx-platform,Stanford-Online/edx-platform,caesar2164/edx-platform,caesar2164/edx-platform,caesar2164/edx-platform