Adjust licensing in readme to reflect reality

Author: nagisa

psm/README.mkd

@@ -489,7 +489,7 @@ PSM is licensed under either of
 
  * Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or
    http://www.apache.org/licenses/LICENSE-2.0)
- * ISC license ([LICENSE-ISC](LICENSE-ISC) or
-   http://opensource.org/licenses/ISC)
+ * MIT license ([LICENSE-MIT](LICENSE-MIT) or
+   http://opensource.org/licenses/MIT)
 
 at your option.