[3.0] better autoloading with PSR-4

[panique]

The current standard in autoloading is probably to do it via Composer's PSR-4 autoloader.

More here: https://getcomposer.org/doc/04-schema.md#autoload

The most simply implementation would be (in composer.json):

{
    "autoload": {
        "psr-4": { "": "src/" }
    }
}

This would always look into src/ folder for any files. To have the autoloader look into multiple folders, the syntax would be:

        "psr-4": { "": ["src/", "lib/"] }

[panique]

Better: Namespace!
"psr-4": { "Mini\\": "Mini/" }

[panique]

Done in develop branch. Better version will come !