Laravel 5.3: How to save images - Is Intervention still available?

I began to use Laravel 5.3, wondering if Intervention is still compatible or not.

I followed the documentation, but I keep getting an error message, saying that

Class 'Intervention\Image\ImageServiceProvider' not found

I simply added Intervention\Image\ImageServiceProvider::class into $providers and also added 'Image' => Intervention\Image\Facades\Image::class into $aliases. Then, I began to see the error message.

When I was using Laravel 5.2, this didn't happen, as far as I remember.

Any advice will be appreciated!

via Chebli Mohamed