Add license block to README.

README.md

@@ -119,4 +119,24 @@ The following properties are available within an <ahk_for_each> tag:
 * _Topic_ - The URL of the forum topic.
 * _Source_ - The optional download URL.
 
+License
+-------
+
+Copyright 2011 Anthony Zhang <azhang9@gmail.com>
+
+This file is part of AutoHotkey.net Website Generator. Source code is available at <https://github.com/Uberi/AutoHotkey.net-Website-Generator>.
+
+AutoHotkey.net Website Generator is free software: you can redistribute it and/or modify
+it under the terms of the GNU Affero General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU Affero General Public License for more details.
+
+You should have received a copy of the GNU Affero General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
 [AutoHotkey Forums]: http://www.autohotkey.com/forum/