added transition state

[ryanflorence]

pinterest example almost works now, just need to
add the omitted path searching to the route
matching.

this isn’t sending the state to transition hooks
but totally should

[ryanflorence]

I like transitionState the most.

• request has a lot of prior meaning we'd be swimming up stream to explain to people
• transitionContext has a little bit of prior meaning with context in React, and its not quite the same
• transitionInfo I like but ...
• transitionState completely mirrors the ignored state feature of pushState, just state would be a good name outside of React, but inside of React I like the transition prefix. I don't think it will take as much to understand as the other names.

[agundermann]

transitionState makes most sense to me, too.

Another one:

• payload: as in request payload. Originally used in Support additional state that is not in the URL #828 (not sure why he changed it to data)

[mjackson]

What if we just kept it on location.state ? key would be part of this.

[agundermann]

Just calling it state might be a bit confusing since this is different from history.state and key (used one time only instead of being persisted). I imagine we might want to add a persistent state (built on top of key) in the future.

[ryancole]

Does this relate to the issue regarding the static transition functions not being able to make use of non-singleton flux stores on props, etc?