feature: Add a redirects mapping parameter

[Dabolus]

This is to be considered a proposal/proof of concept, not a real PR.

The router helper is really great and useful, and I've been using it a lot. However, almost every time I use it, I also find myself having to implement some sort of redirect (for example, redirecting users from / to /view1). My proposal is to add an optional "redirects mapping" parameter, that will automatically handle redirects passed to it. What do you think? Would it add too much complexity?

Example usage of my current implementation:

installRouter(callback, [
  {
    from: '/',
    to: '/view1'
  },
  {
    // Also supports arrays
    from: [
      '/randompage1',
      '/randompage2'
    ],
    to: '/view2'
  }
]);

[keanulee]

Interesting idea, though this wouldn't handle cases where users cmd+click's to open in new tab or if the user navigates directly to the "from" URL. Those cases would have to be handled by some script, perhaps in a history.replaceState() in the function you pass to installRouter().

[Dabolus]

Actually, this check should handle those cases too, as it is run when the router is installed

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