Add scene module

This will eventually replace space-pen, which depends on jQuery and is too slow.
Add views and events to scene
Add outlets
Add enter/exit hooks and subview manipulations to scene
Remove a newline
Convert camel case attributes to snake case
Make ViewBuilder::subview take outlet name
Add default content to View
Switch to child-based replaceWith
Switch to static content function
Switch app to scene
Switch internal error view to scene
Switch new topic view to scene
Remove a console.log
Convert carousel views to scene
Switch to document fragments for scene
Switch discuss view to scene
Switch explore view to scene
Switch home view to scene
Fix some bugs in discuss view