Fixed UV order in Sphere

The order of U was backwards and was set as negative to fix. It is now
properly reversed.
Fix setAtlasTile method to properly update UVs
Merge pull request #986 from Davhed/sphere-uv-fix

Fixed U order in Sphere
Merge pull request #987 from Davhed/set-atlas-tile-fix

Fix setAtlasTile method to properly update UVs