added test

Author: Christian Hammers

src/test/java/org/apache/commons/codec/digest/B64Test.java

@@ -21,6 +21,11 @@
 
 public class B64Test {
 
+    @Test
+    public void testB64T() {
+        assertEquals(64, B64.B64T.length());
+    }
+
     @Test
     public void testB64from24bit() {
         StringBuilder buffer = new StringBuilder("");