[removed] RouteStore

[added] Router.PathState for keeping track of the current URL path
[added] Router.RouteLookup for looking up routes
[added] Router.Transitions for transitioning to other routes
[added] Pluggable scroll behaviors
[changed] <Routes preserveScrollPosition> => <Routes scrollBehavior>
[removed] <Route preserveScrollPosition>
[removed] Router.transitionTo, Router.replaceWith, Router.goBack
Merge branch 'master' into remove-route-store

Conflicts:
	modules/actions/LocationActions.js
	modules/components/Routes.js
	modules/locations/HistoryLocation.js
	modules/locations/MemoryLocation.js
	modules/mixins/PathListener.js
	modules/stores/PathStore.js
	modules/utils/makeHref.js
[added] <Routes fixedPath>
Move makePath/Href to Router.Transitions
[added] <Routes location="none">
Update tests
Add tests for DefaultRoute and NotFoundRoute
Add tests for ActiveDelegate
More tests
More tests
Rename initialState => initialActiveState
Add getActiveRoute
Add <Link> component tests

Also, removed deprecated static <Link> props.
Add <Routes> tests
More tests, finished porting
Merge branch 'remove-route-store'

Conflicts:
	modules/components/Routes.js