Fill router reducer with initial data

[DimitryDushkin]

1. It will be nice to fill up router state with corresponding initial data (default value).
2. (again) Initial LOCATION_CHANGE action is still misleading and should be removed:
   1. Location is actually not changing on page refresh for example
   2. Also if you opening some link from address bar location is not changing from about: blank by default (it should be configured), so location is not actually changing.
   3. History API does not fire such event on loading

[timdorr]

Please don't open duplicate issues. #5038

[DimitryDushkin]

@timdorr I've added one more proposal (didn't present in duplicate) and you didn't answered to my arguments in prior issue, so I've added them to this related issue.

[DimitryDushkin]

Anyway what's the point in closing issues without discussion and agreement?

[timdorr]

Because it's an alpha. Things will change and we haven't even figured out the basics, such as time travel. Give it time to solidify before going after the base semantics. The structure is going to change drastically very soon (once #4717 or something like it lands).

[DimitryDushkin]

Oh, I see. Thank you.