Make enabled an optional attribute.
Move dataService => dataService.state
Start undo / redo

Models are updated in background, but inputs lose reference to data after undo, so frontend becomes unresponsive.
Modals!

For now, the changes you make in the modal don't actually do anything. But this will change soon :)
change default server port
Fix drag and drop.

!!!!!!!

Yeah, it was that annoying.
Merge pull request #7 from kolemannix/undo-redo

Merge undo-redo