Parsing support for class+method callable and added --filename option

[vaites]

Laravel suggest to add macros using service providers. If you create the macro using a closure or a funcion the helper works well but fails if you use a callable with an array of class+method the helper thows an exception:

In MacrosCommand.php line 98:

Symfony\Component\Debug\Exception\FatalThrowableError]                                      
Type error: ReflectionFunction::__construct() expects parameter 1 to be string, array given

Example code:

<?php

namespace App\Providers;

use Illuminate\Support\Collection;
use Illuminate\Support\ServiceProvider;

class CollectionServiceProvider extends ServiceProvider
{
    public function register()
    {
        Collection::macro('test1', [$this, 'test1']);
        Collection::macro('test2', [static::class, 'test2']);
    }

    /**
     * Test
     *
     * @return int
     */
    public function test1()
    {
        return time();
    }

    /**
     * Static test
     *
     * @return int
     */
    public static function test2()
    {
        return time();
    }
}

This makes the code more readable, so this PR fixes the exception thrown by the helper trying parse this behaviour.

I also added the --filename= option to command (like Laravel IDE Helper) that allows users to change the filename and path without publishing any additional config file (perfect for composer scripts).

Thanks @KristofMorva

[KristofMorva]

Looks good, thanks! ;)

[vaites]

Thanks!