New API (again)
Add invariant
Add example to docblock
Use contexts in RouteHandler
added some runRouter tests
[added] ActiveRouteHandler
dynamic segments
render null w/o active handler
AN EXAMPLE WORKS
update jsx loader
move makePath to Router not RouteHandler
add failing test
better `<ActiveRouteHandler/>`

- if used twice in one owner, it's the same thing
- works more than the initial render
Router test stubs
update the master-detail example
Consistent anonymous function declaration style
Add makePath definition to route handler class
Use _owner to lookup active child handler
Add back Router#makePath
Use a factory to prevent warnings in 0.12