archive/tar: spell license correctly in example

Change-Id: Ice85d161f026a991953bd63ecc6ec80f8d06dfbd
Reviewed-on: https://go-review.googlesource.com/17901
Run-TryBot: Joe Tsai <joetsai@digital-static.net>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

src/archive/tar/example_test.go

@@ -26,7 +26,7 @@ func Example() {
 	}{
 		{"readme.txt", "This archive contains some text files."},
 		{"gopher.txt", "Gopher names:\nGeorge\nGeoffrey\nGonzo"},
-		{"todo.txt", "Get animal handling licence."},
+		{"todo.txt", "Get animal handling license."},
 	}
 	for _, file := range files {
 		hdr := &tar.Header{
@@ -76,5 +76,5 @@ func Example() {
 	// Geoffrey
 	// Gonzo
 	// Contents of todo.txt:
-	// Get animal handling licence.
+	// Get animal handling license.
 }