update ui in billboards, labels, camera and materials
update outdated pictures
add GeoJSON/TopoJSON example
cleanup
Create SampleData folder
Merge branch 'master' into scrubSandcastle
cleanup
fix camera demo
Merge branch 'master' into scrubSandcastle
move models
Merge pull request #1905 from AnalyticalGraphicsInc/scrubSandcastle

Update UI in Billboards, Labels and Camera Sandcastle examples
Merge remote-tracking branch 'origin/master' into gltf-8