Add encrypt-decrypt script

[SiebeVE]

No description provided.

[arnedesmedt]

Why is this needed?

[SiebeVE]

For debugging purposes, because we can see the encrypted string, but sometimes we want to know if the value is correctly encrypted (and can be decrypted with the secret).
This is the script that just uses the internal code.
The composer part then make sure we can do ./vendor/bin/ads-vo-encyrpt-decrypt.php