Add name attribute on magic constants

Here is a little contribution to add automatic name on magic constant nodes.

With unit tests 
    PHPUnit 3.7.31 by Sebastian Bergmann.

    .......

    Time: 187 ms, Memory: 2.00Mb

    OK (7 tests, 7 assertions)

Here is a sample of result in real condition


    [args] => Array
        (
            [0] => PhpParser\Node\Arg Object
                (
                    [subNodes:protected] => Array
                        (
                            [value] => PhpParser\Node\Scalar\MagicConst\File Object
                                (
                                    [subNodes:protected] => Array
                                        (
                                            [name] => PhpParser\Node\Name Object
                                                (
                                                    [subNodes:protected] => Array
                                                        (
                                                            [parts] => Array
                                                                        (
                                                                            [0] => __FILE__
                                                                        )

                                                                )

                                                            [attributes:protected] => Array
                                                                (
                                                                )

                                                        )

                                                )

                                            [attributes:protected] => Array
                                                (
                                                    [startLine] => 185
                                                    [endLine] => 185
                                                )

                                        )

                                    [byRef] => 
                                )

                            [attributes:protected] => Array
                                (
                                    [startLine] => 185
                                    [endLine] => 185
                                )

                        )

                )
                



BTW, thanks for your parser, its really a pleasure to implement it. I did it only on one day to replace my old parser in my PHP Reflect v2 project.