Remove RouteStore

This PR is a little messy (apologies) because I had to merge with @gaearon's changes that we merged into master, but it should preserve everything he did WRT scrolling behavior.

There may be a few bugs. Please run through the examples and let me know what you find!

@rpflorence checklist edit:

- [x] data-flow example: click on a taco, refresh, page is blank, introduced by  8b787037dead245c3d3a49ab411e29a7bb5cde8a
- [x] master-detail and transitions examples: `Router.transitionTo` is not a function (should probably just search all examples to fix these)
- [x] all examples: if you refresh at a route and then use the back button it doesn't work (works fine, however, before a refresh, simple-master-detail is a good one to see this behavior)
- [x] ~~partial app loading (while you're in there fix this maybe?! j/k we can worry about this later)~~