Ctrl-z does not undo changes via the side panel.

[dceejay]

If the dashboard is updated using the side panel - eg re-ordering widgets, you cannot then use ctrl-z to undo that action.

RED.history.push( actions need to be added throughout the ui_base.html to manually add these events to the history so they can be undone.

• [x] add basic undo for widget positions - 866d28dcec7d0b82c4ef1972c6fb5647928034c7
• [ ] Add callback to core to allow sidebar to also update positions
• [ ] Add undo to other visual elements like theme