more work on render model scenes
Merge branch 'master' of https://github.com/highfidelity/hifi into modelSceneRendering
actually only pick programs once
some cleanup
Merge pull request #3788 from ZappoMan/modelSceneRendering

More work on model scene rendering
Merge branch 'master' of https://github.com/highfidelity/hifi into entities_userdata
String specific macros