Cache redirects?

[makew0rld]

Add some more functions to the cache package so that it can cache redirects and load them, and have handleURL try to use that, to prevent requesting redirects each time.

The problem is how can the user easily clear the cache? For example this would break the redirect hell test. One way would be a clear cache command, but still there could be unexpected behaviour.

[makew0rld]

A good related thing to do would be to auto-accept redirects that just add a slash, and remember them. This would improve the UX a lot for those instances. Any other redirect after that initial one would show up to the user though, even if it just adds another slash, or redirects back to the non-slash page, as a malicious attack.

[makew0rld]

Only permanent redirects, status code 31, should be accepted.

[makew0rld]

Permanent redirects are now cached for the browser session, if the user accepts them. Auto-accepting redirects that just add a slash could be an issue for another time.