Update copyright notice

cvrebert · cvrebert · commit acc6dc4fceac · 2016-07-23T18:20:22.000-07:00
Ports twbs/bootstrap#19936 to bootstrap-sass
diff --git a/LICENSE b/LICENSE
@@ -1,6 +1,7 @@
 The MIT License (MIT)
 
-Copyright (c) 2013-2016 Twitter, Inc
+Copyright (c) 2011-2016 Twitter, Inc
+Copyright (c) 2011-2016 The Bootstrap Authors
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
