added email change strategies

lib/User/Contracts/MailChangeStrategyInterface.php

@@ -0,0 +1,9 @@
+<?php
+namespace Da\User\Contracts;
+
+interface MailChangeStrategyInterface extends StrategyInterface
+{
+    const TYPE_INSECURE = 0;
+    const TYPE_DEFAULT = 1;
+    const TYPE_SECURE = 2;
+}

lib/User/Contracts/StrategyInterface.php

@@ -1,15 +1,10 @@
 <?php
 namespace Da\User\Contracts;
 
-/**
- *
- * StrategyInterface.php
- *
- * Date: 3/12/16
- * Time: 16:23
- * @author Antonio Ramirez <hola@2amigos.us>
- */
 interface StrategyInterface
 {
-
+    /**
+     * @return bool
+     */
+    public function run();
 }