support impersonation tokens

Author: gaooulong

lib/Gitlab/Api/Users.php

@@ -253,4 +253,49 @@ public function email($id)
     {
         return $this->get('user/emails/'.$this->encodePath($id));
     }
+
+    /**
+     * @param int $user_id
+     * @return mixed
+     */
+    public function userImpersonationTokens($user_id)
+    {
+        return $this->get('users/'.$this->encodePath($user_id).'/impersonation_tokens/');
+    }
+
+    /**
+     * @param int $user_id
+     * @param int $impersonation_token_id
+     * @return mixed
+     */
+    public function userImpersonationToken($user_id, $impersonation_token_id)
+    {
+        return $this->get('users/'.$this->encodePath($user_id).'/impersonation_tokens/'.$this->encodePath($impersonation_token_id));
+    }
+
+    /**
+     * @param int $user_id
+     * @param string $name
+     * @param array $scopes
+     * @param null $expires_at
+     * @return mixed
+     */
+    public function createImpersonationToken($user_id, $name, array $scopes, $expires_at = null)
+    {
+        return $this->post('users/'.$this->encodePath($user_id).'/impersonation_tokens', array(
+            'name' => $name,
+            'scopes' => $scopes,
+            'expires_at' => $expires_at
+        ));
+    }
+
+    /**
+     * @param int $user_id
+     * @param int $impersonation_token_id
+     * @return mixed
+     */
+    public function removeImpersonationToken($user_id, $impersonation_token_id)
+    {
+        return $this->delete('users/'.$this->encodePath($user_id).'/impersonation_tokens/'.$this->encodePath($impersonation_token_id));
+    }
 }