Allow to delete source images

Problem/Motivation

Our customer wants to be able to remove files from drupal and rokka.

Steps to reproduce

Try to delete a file in drupal the rokka file still exists.

Proposed resolution

Implement
Deleting source images with binary hash
The same binary hash can have different entries in rokka, if they have different dynamic metadata. With this command you can delete all of them at once

curl -X DELETE 'https://api.rokka.io/sourceimages/mycompany?binaryHash=03b3e8a0bdd76ef55...'
$client = \Rokka\Client\Factory::getImageClient('mycompany', 'apiKey');

$isDeleted = $client->deleteSourceImagesWithBinaryHash('03b3e8a0bdd76ef55c021066642c9d2fa9c02799');

var_dump($isDeleted);

And a delete hook.