add files

Author: taylorotwell

src/Illuminate/Contracts/Database/Eloquent/Castable.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace Illuminate\Contracts\Database\Eloquent;
+
+interface Castable
+{
+    /**
+     * Get the name of the caster class to use when casting from / to this cast target.
+     *
+     * @return string
+     */
+    public static function castUsing();
+}