Allow passing in the title from state

[mvhenten]

This would allow me to pass in "title" from "state". Furthermore, if I do so, I can avoid the dependency on document and use page.js to route server-side rendering.

[samccone]

This is a reasonable change, however it is breaking since someone could be using state.title for something else.

For this PR to land we need to do the following:

1. do a major semver bump.
2. update the documentation around this feature.