Data editor paste support

[eug3nix]

It should be possible to copy cell range and paste it back to the data editor grid.
Imagine this use case:
User selects a whole row in data editor, then clicks "Add", the new blank row is generated.
User then clicks on that new blank row and pastes (either via ctrl-v or using a context menu "Paste" option which we don't have yet).

As a result the new row should be populated with copied cells.

Figure out how to handle these cases:
user paste data that contain only a part of necessary columns
user paste data that was copied from multiple rows

Check how spreadsheet software handles that. Ideally we should replicate that behavior so there are no surprises for the user

[eug3nix]

Note: most of the mentioned functionality was already covered in c0d9da9
The only obviously missing thing is "Paste" option in the context menu