First work toward moving to a Swing UI for the simulator.

src/main/java/com/loomcom/symon/exceptions/MemoryAccessException.java

@@ -4,7 +4,7 @@ package com.loomcom.symon.exceptions;
  * Exception that will be thrown if access to memory or IO cannot be
  * accessed.
  */
-public class MemoryAccessException extends Exception {
+public class MemoryAccessException extends SymonException {
   public MemoryAccessException(String msg) {
     super(msg);
   }