Update and rename LICENSE.html to LICENSE

LICENSE.html → LICENSE

@@ -175,7 +175,7 @@
 
    END OF TERMS AND CONDITIONS
 
-   Copyright 2014-2015 Vaadin Ltd.
+   Copyright 2014-2016 Vaadin Ltd.
 
    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.