Throw exception if display couldn't be created.
Fixed select box list select when first opened.
Merge remote-tracking branch 'origin/master'
Added concept of target actor, separate from the actor the action is added to.

This allows an action to be added to one actor but affect another. This is useful to create a sequence of actions that affect many different actors. Previously this would require adding actions to each actor and using delays to get them to play in the correct order.