README and docblock updates for Str::encrypt() and Str::decrypt() methods

Author: PHLAK

README.md

@@ -893,14 +893,19 @@ $string->bcrypt(['salt' => 'NaClNaClNaClNaClNaClNaCl']); // Returns '$2y$10$NaCl
 > Encrypt the string.
 
 ```php
-Twine\Str::encrypt( string $key, [ string $cipher = 'aes-128-gcm' ] ) : Twine\Str
+Twine\Str::encrypt( string $key, [ string $cipher = 'AES-128-CBC' ] ) : Twine\Str
 ```
 
 | Parameter | Description            |
 | --------- | ---------------------- |
 | `$key`    | The key for encrypting |
 | `$cipher` | The cipher method      |
 
+Supported cipher methods:
+
+  - `AES-128-CBC` (default)
+  - `AES-256-CBC`
+
 #### Example
 
 ```php
@@ -915,14 +920,19 @@ $string->encrypt('secret'); // Returns something like '$DZpEm9ZFec9ybxF7$y2rc62E
 > Decrypt the string.
 
 ```php
-Twine\Str::decrypt( string $key, [ string $cipher = 'aes-128-gcm' ] ) : Twine\Str
+Twine\Str::decrypt( string $key, [ string $cipher = 'AES-128-CBC' ] ) : Twine\Str
 ```
 
 | Parameter | Description            |
 | --------- | ---------------------- |
 | `$key`    | The key for decrypting |
 | `$cipher` | The cipher method      |
 
+Supported cipher methods:
+
+  - `AES-128-CBC` (default)
+  - `AES-256-CBC`
+
 #### Example
 
 ```php

src/Traits/Encryptable.php

@@ -19,11 +19,11 @@ trait Encryptable
      * Encrypt the string.
      *
      * @param string $key    The key for encrypting
-     * @param string $cipher The cipher method (default: 'AES-128-CBC')
+     * @param string $cipher The cipher method
      *
      * Supported cipher methods:
      *
-     *   - AES-128-CBC
+     *   - AES-128-CBC (default)
      *   - AES-256-CBC
      *
      * @throws \PHLAK\Twine\Exceptions\EncryptionException
@@ -56,11 +56,11 @@ public function encrypt(string $key, string $cipher = 'AES-128-CBC') : self
      * Decrypt the string.
      *
      * @param string $key    The key for decrypting
-     * @param string $cipher The cipher method (default: 'AES-128-CBC')
+     * @param string $cipher The cipher method
      *
      * Supported cipher methods:
      *
-     *   - AES-128-CBC
+     *   - AES-128-CBC (default)
      *   - AES-256-CBC
      *
      * @throws \PHLAK\Twine\Exceptions\DecryptionException