Normalize spelling to US English in comments.

Author: garydgregory

src/test/java/org/apache/commons/codec/binary/Base32Test.java

@@ -246,7 +246,7 @@ public void testConstructors() {
         base32 = new Base32(-1, new byte[] {});
         base32 = new Base32(32, new byte[] {});
         base32 = new Base32(32, new byte[] {}, false);
-        // This is different behaviour than Base64 which validates the separator
+        // This is different behavior than Base64 which validates the separator
         // even when line length is negative.
         base32 = new Base32(-1, new byte[] { 'A' });
         try {