updated readme

added usage instructions

README.md

@@ -21,3 +21,16 @@ To install the package using Composer, run the following command:
 ```bash
 composer require hpz937/encryption:1.0.0
 ```
+
+### Usage
+```php
+$key = "really_strong_encryption_key";
+$dataEncryptor = new DataEncryptor($key);
+
+$stringToEncrypt = "data you would like to encrypt"
+$encryptedData = $dataEncryptor->encrypt($stringToEncrypt);
+var_dump($encryptedData);
+
+$decryptedData = $dataEncryptor->decrypt($encryptedData);
+var_dump(decryptedData);
+```