Add README and GPLv3 LICENSE and mention license in every source file

1 files changed, 4 insertions, 0 deletions

diff --git a/sauvola.go b/sauvola.go
index 3ba4359..5a9be03 100644
--- a/sauvola.go
+++ b/sauvola.go
@@ -1,3 +1,7 @@
+// Copyright 2019 Nick White.
+// Use of this source code is governed by the GPLv3
+// license that can be found in the LICENSE file.
+
 package preproc
 
 import (