Data Table modifications

[borondics]

I think some of the phrasing and behaviour of Data Table could be improved. Since it is a very heavily used widget I think it would be great to do (some) of the following.

What's your use case?

• The "Variables" section could be renamed to "Visualization", which is more descriptive to me.
• The Restore Original Order button is active even if instances are in the original order. Deactivating it (similar to the Send Selection button behaviour) would be nice in those cases.
• The "Send Selection" button changes its text to "Send Automatically" when the checkbox is activated. I think this is confusing. I would simply change the text to "Sending Selection".
• Deselecting a selected row is not intuitive (needs CTRL-leftclick or CMD-leftclick currently). Could it be changed to simply leftclick?

What's your proposed solution?

If this proposal is accepted (and after #6968 is merged) I can work on these (and also update the documentation again).

Are there any alternative solutions?

No.