replaceState support

[MattKunze]

Do you have opinions about adding support to replace state in addition to updating it? It seems like there could be parallel REPLACE_PATH, replacePath exports with internals that mimic the existing functions.

I'm more than happy to come up with a PR, just didn't want to step on any plans that were already in place.

As mentioned in this comment it seems like the history API might be changing as well, though that seems pretty easy to handle.

[jamischarles]

Just switched to this from redux-router. Really like the API. Would also love replaceState. Could even be a simple 3rd param on the updatePath function...

[MattKunze]

Yeah, I don't have strong opinions between adding another action or just extending the current one. Not a huge fan of unnamed ordinal binary flags though, I'd prefer something like: updatePath(path, { noRouterUpdate: false, replaceState: true })

[cappslock]

Came here to say this, more or less.

[jlongster]

This is coming :) I wanted to shake out #40 first, because it changes the core code and this still will have to be rebased. Sorry!

[MattKunze]

Sweet - I'll probably pull my PR in favor of #38 since it does the same thing and handles state at the same time.

[jlongster]

@MattKunze Thanks, sorry for the duplicate work! I'm going to consolidate some of the issues now.