Fixes #1205
Merge branch 'next' of https://github.com/blackberry/GamePlay into next
Removed VisibleSetDefault.cpp/.h and made Scene implement a default VisibleSet
Added support for Node activate as a replacement for visibility.
Merge branch 'next' of https://github.com/blackberry/GamePlay into next
Merge pull request #1256 from seanpaultaylor/next

Next