added Undo/Redo Test on initial Stack
added Undo/Redo Test on initial Stack

limetext/lime-backend,limetext/lime-backend,ch1bo/lime-backend,codex8/lime-backend,limetext/lime-backend,ch1bo/lime-backend,bj7/lime-backend,codex8/lime-backend,bj7/lime-backend,codex8/lime-backend,bj7/lime-backend,ch1bo/lime-backend,bj7/lime-backend,codex8/lime-backend,limetext/lime-backend,limetext/backend,ch1bo/lime-backend