Function create_from_phpdoc_kphp_generic_new_syntax

a new syntax is `@kphp-generic T1, T2` every T may have extends_hint: "T: callable" / "T: BaseClass" every T may have def_hint: "T = mixed", "T = \VK\Err" (if both, it looks like "T: Err = Err") (@param tags depending on T's are parsed afterward, like regular @param: T will be interpreted as TypeHintGenericT)