Update LICENSE

LICENSE

@@ -1,6 +1,9 @@
 MIT License
 
-Copyright (c) 2018 ShowdownJS
+Copyright (c) 2018 ShowdownJS <http://showdownjs.com>
+
+Markdown (TM) Copyright (c) 2004, John Gruber <http://daringfireball.net/>
+
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
@@ -9,8 +12,12 @@ to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:
 
-The above copyright notice and this permission notice shall be included in all
-copies or substantial portions of the Software.
+ * The above copyright notice and this permission notice shall be included in all
+   copies or substantial portions of the Software.
+   
+ * Neither the name "Markdown" nor the names of its contributors may
+   be used to endorse or promote products derived from this software
+   without specific prior written permission.
 
 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,