Bugfixes, change logger, update copyright

- IR field in status panel now correctly displays the next instruction
  to be executed, instead of the instruction that was just executed.

- Switched from built-in Java util logger to Logback

- Updated all copyright strings to 2016

src/main/java/com/loomcom/symon/ui/TraceLog.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014 Seth J. Morabito <web@loomcom.com>
+ * Copyright (c) 2016 Seth J. Morabito <web@loomcom.com>
  *                    Maik Merten <maikmerten@googlemail.com>
  *
  * Permission is hereby granted, free of charge, to any person obtaining
@@ -113,4 +113,8 @@ public class TraceLog extends JFrame {
         traceLogTextArea.setEnabled(true);
     }
 
+    public boolean shouldUpdate() {
+        return isVisible() && traceLogTextArea.isEnabled();
+    }
+
 }