exception, to do with CPU visualisation I think

[mbway]

I think this was triggered by closing the CPU visualisation but I can't remember exactly. Pretty sure we have had these kinds of exceptions from the CPU visualisation before?

Thread:  JavaFX Application Thread
At:      2016-09-19 17:43:39.840
Cause:   null
Message: "Timer already cancelled."

java.lang.IllegalStateException: Timer already cancelled.
    at java.util.Timer.sched(Timer.java:397)
    at java.util.Timer.schedule(Timer.java:193)
    at simulizer.ui.components.CPU.lambda$showText$0(CPU.java:110)
    at javafx.animation.Animation.impl_finished(Animation.java:1132)
    at javafx.animation.AnimationAccessorImpl.finished(AnimationAccessorImpl.java:49)
    at com.sun.scenario.animation.shared.SingleLoopClipEnvelope.timePulse(SingleLoopClipEnvelope.java:103)
    at javafx.animation.Animation.impl_timePulse(Animation.java:1102)
    at javafx.animation.Animation$1.lambda$timePulse$24(Animation.java:186)
    at java.security.AccessController.doPrivileged(Native Method)
    at javafx.animation.Animation$1.timePulse(Animation.java:185)
    at com.sun.scenario.animation.AbstractMasterTimer.timePulseImpl(AbstractMasterTimer.java:344)
    at com.sun.scenario.animation.AbstractMasterTimer$MainLoop.run(AbstractMasterTimer.java:267)
    at com.sun.javafx.tk.quantum.QuantumToolkit.pulse(QuantumToolkit.java:506)
    at com.sun.javafx.tk.quantum.QuantumToolkit.pulse(QuantumToolkit.java:490)
    at com.sun.javafx.tk.quantum.QuantumToolkit.lambda$runToolkit$346(QuantumToolkit.java:319)
    at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
    at com.sun.glass.ui.gtk.GtkApplication._runLoop(Native Method)
    at com.sun.glass.ui.gtk.GtkApplication.lambda$null$450(GtkApplication.java:139)
    at java.lang.Thread.run(Thread.java:745)