Context menu should offer to add new task when taskStore is empty

[jsakalos]

There is no UI way to add a task to the completely empty Gantt. We should have a context menu (right-clicking on empty left grid) that would allow for that.

Forum post

https://forum.bryntum.com/viewtopic.php?f=43&t=23781&p=117757#p117757

Hey team,

I have two questions regarding the Gantt chart. I see that if there are some tasks, I can right-click and add a task below or above, but if there is no data in the Gantt chart, how can I add a new task to this empty chart? I want to change the color of "SAVE CHANGES" button if any edit(add task, deps etc.) is applied to the chart, how can this be implemented?

Thank you