Fixing typo in exception text as reported by Eric Fung in CODEC-103

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/codec/trunk@966309 13f79535-47bb-0310-9956-ffa450edef68

Author: hen

src/java/org/apache/commons/codec/binary/Hex.java

@@ -164,7 +164,7 @@ public static String encodeHexString(byte[] data) {
     protected static int toDigit(char ch, int index) throws DecoderException {
         int digit = Character.digit(ch, 16);
         if (digit == -1) {
-            throw new DecoderException("Illegal hexadecimal charcter " + ch + " at index " + index);
+            throw new DecoderException("Illegal hexadecimal character " + ch + " at index " + index);
         }
         return digit;
     }