CI 3.1.1 Index/index gives 404

PHP 4 constructors are deprecated in PHP 7.0, but at least until they are removed such Index::index names won't be just a normal combination.
So its not usable, the same way as it wasn't in the past..
Once this PHP 4 constructors are fully removed in some future 7.x or even at PHP 8, this combination will be ok I think to exists and work.

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