Some code cleanup and copyright cleanup. [skip ci]

app/Models/TransactionType.php

@@ -3,8 +3,10 @@
  * TransactionType.php
  * Copyright (C) 2016 thegrumpydictator@gmail.com
  *
- * This software may be modified and distributed under the terms
- * of the MIT license.  See the LICENSE file for details.
+ * This software may be modified and distributed under the terms of the
+ * Creative Commons Attribution-ShareAlike 4.0 International License.
+ *
+ * See the LICENSE file for details.
  */
 
 declare(strict_types = 1);