Improve history states (#932)

* Add some more history states

* Fix undo whilst drawing

* Paste image history

* Toggle output and preview history

* Code review nits

* Remove extra '{'

* Fix typo

* Fix about.toml

Co-authored-by: Keavon Chambers <keavon@keavon.com>

node-graph/gcore/src/ops.rs

@@ -59,7 +59,7 @@ pub mod dynamic {
 				alloc::boxed::Box::new($node.eval(($(*dyn_any::downcast::<$t>($arg).unwrap()),*)) ) as Dynamic
 			}
 		)else*
-		else{
+		else {
 			panic!("Unhandled type"); // TODO: Exit neatly (although this should probably not happen)
 		}
 	};