GH-352 Make OneSix instance update downloads cancellable

application/InstanceWindow.cpp

@@ -212,6 +212,7 @@ void InstanceWindow::onFailed(QString reason)
 void InstanceWindow::onProgressRequested(Task* task)
 {
 	ProgressDialog progDialog(this);
+	progDialog.setSkipButton(true, tr("Abort"));
 	m_proc->proceed();
 	progDialog.execWithTask(task);
 }

application/MainWindow.cpp

@@ -1185,6 +1185,7 @@ void MainWindow::finalizeInstance(InstancePtr inst)
 				});
 		if(update)
 		{
+			loadDialog.setSkipButton(true, tr("Abort"));
 			loadDialog.execWithTask(update.get());
 		}
 	}