store subtab state in query string
Merge branch 'master' into sandcastleTabState
avoid jshint violation
Merge branch 'master' into sandcastleTabState
rename subtab to label
only change history when new demo is loaded
Merge pull request #1223 from AnalyticalGraphicsInc/sandcastleTabState

Link to sandcastle subtab state
Merge remote-tracking branch 'origin/master' into gltf