Update LICENSE

Fixed grammatical error

Author: sandip2224

LICENSE

@@ -1,6 +1,6 @@
 * Code is GPL v3 licensed:
 This Source Code is subject to the terms of the GNU General Public License, v. 3.0.
-If a copy of the GPL was not distributed with this file, You can obtain one at http://www.gnu.org/licenses/gpl-3.0.txt
+If a copy of the GPL was not distributed with this file, you can obtain one at http://www.gnu.org/licenses/gpl-3.0.txt
 
 * Assets and content designed for Mozilla BrowserQuest are licensed under CC-BY-SA 3.0:
 http://creativecommons.org/licenses/by-sa/3.0/