Drop support of too old PHP versions

Usually you want to build a framework to support the versions of PHP most likely to be installed on servers at the time of release. Currently, PHP 5.3 accounts for almost half of the websites using PHP (per http://w3techs.com/technologies/details/pl-php/5/all ). The scary part is that 5.2 accounts for nearly as many sites as 5.4, but once you go to 5.5+, you're talking about just over 5%.

While there is some room for a coordinated effort by PHP framework developers to push the server vendors/operators to upgrade their PHP versions, most developers have to look at their potential user base to determine what version they use as their minimum supported version.

With that said, there's nothing stopping you from using a newer version of PHP on your server, or from using all of those new features in your own code. Even if the minimum version for CI was increased to 5.6, I don't think you'd see a 3.x release with the CI code refactored/rewritten to namespace the core classes and libraries.

Bonfire

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