Make gui.Caret, gui.UndoManager and ops.Operation 100% typed.
Make gui.TrivialUndoManager and gui.UndoStateRules 100% typed.
Merge pull request #365 from vandenoever/typing

Add more typing information to some classes
Adapt PullboxOperationRouter to batch processing signals

Missing from 26a9252edbe9295fc1c2f027096d6d2f22ea6f52