[NFR] add aspect ratios validation for Validator/Files

Right now we can set `minResolution` and `maxResolution` options.

But in responsive design is more useful have images with same aspect ratios.
For example if you show list of cards with images.

the code could be looks like that:

```php
'aspectRatio' => [
  'file' => '16by9' // or 16x9
]
```