Added a note on forking

Author: Jason Frame

README

@@ -42,3 +42,9 @@ Remember to include jquery.tipsy.js *after* including the main jQuery library.
 </script>
 
 Please refer to the docs directory for more examples and documentation.
+
+== A NOTE ON FORKING:
+
+By forking this project you hereby grant permission for any commits to your fork to be
+merged back into this repository and, with attribution, be released under the terms of
+the MIT License.