Clarify that utils/launch.sh is MPL-2.0

Also, note in the top-level license file that the default noVNC
license for files that are not explicitly marked or mentioned in
the LICENSE.txt file are by default MPL-2.0 licensed.

utils/launch.sh

@@ -1,5 +1,9 @@
 #!/usr/bin/env bash
 
+# Copyright 2016 Joel Martin
+# Copyright 2016 Solly Ross
+# Licensed under MPL 2.0 or any later version (see LICENSE.txt)
+
 usage() {
     if [ "$*" ]; then
         echo "$*"