Update license text

src/input/Interfaces.ts

@@ -1,3 +1,8 @@
+/**
+ * Copyright (c) 2017 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
 export interface IMouseZoneManager {
   add(zone: IMouseZone): void;
   clearAll(): void;

src/input/MouseZoneManager.ts

@@ -1,3 +1,8 @@
+/**
+ * Copyright (c) 2017 The xterm.js authors. All rights reserved.
+ * @license MIT
+ */
+
 import { IMouseZoneManager, IMouseZone } from './Interfaces';
 import { ITerminal } from '../Interfaces';
 import { getCoords } from '../utils/Mouse';