Tests for AddressDecoder. Fixed a bug in isComplete().

src/main/java/com/loomcom/lm6502/MemoryRangeException.java

@@ -3,7 +3,7 @@ package com.loomcom.lm6502;
 /**
  * Exception that will be thrown if devices conflict in the IO map.
  */
-class MemoryRangeException extends Exception {
+public class MemoryRangeException extends Exception {
 	public MemoryRangeException(String msg) {
 		super(msg);
 	}