Fixed  a problem where B1, b2, etc would still play the animation for B instead of the correct one

DialogMenu.SetDialogClip() is called when the button is clicked, replacing the DialogClip data in the DialogMenu with new audio and animation.  If dialog_clip == null, it creates a new one.  If it's non-null, it
sets the audioclip property for it, and needs to set the animationClip property too.