Bug fix and reword for scrolling feature

[Akeboshiwind]

Does two things:

• Adjusts the wording in the README to better reflect current code
• Fix a bug where pages don't scroll if there's no ajax request made

It does this by changing :route-counter to be just a pure number and not keep track of the route.
Now:

• ::poll checks against the :kee-frame/route which is updated before ::poll is called
• Ajax interceptors are only setup once (a small efficiency gain)
• monitor-requests! is part of the cond-> in ::route-changed which seems a bit cleaner

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I've tested that this works against this repo I created: https://github.com/ake-temp/kee-frame-scroll-repro