added getMinMessageLength and getMaxMessageLength

Author: bschoening

src/main/java/com/privacylogistics/FF3Cipher.java

@@ -140,6 +140,14 @@ public FF3Cipher(byte[] key, byte[] tweak, int radix) {
         this(key, tweak, alphabetForBase(radix));
     }
 
+    public int getMinMessageLength() {
+        return minLen;
+    }
+
+    public int getMaxMessageLength() {
+        return maxLen;
+    }
+
     /**
      * Encrypt a value using default tweak
      * @param plaintext   a plaintext to encrypt