Fix ManyPlanetsDeep demo so
(1) It doesn't generate a perf warning about not using attrib 0
(2) It doesn't try to render with incomplete textures
Merge branch 'master' of git://github.com/KhronosGroup/WebGL into fix-ManyPlanetsDeep
Merge pull request #234 from greggman/fix-ManyPlanetsDeep

Fix many planets deep