This refactor includes only these general changes:
- avoid `id( new A() )->b()` and adopt `( new A() )->b()` - since 5.4
- avoid `dirname(__FILE__)` and adopt `__DIR__` - since PHP 5.3
- avoid `$foo ? $foo : $default` and adopt `$foo ?: $default` - since PHP 5.3
- avoid `self::class` and adopt `__CLASS__` - since 5.0
To better understand and comment these old PHP features, see:
https://we.phorge.it/T15158
Note that all directories like __tests__ were skipped.
Ref T15158
Ref P6