Feature request: Transpose multiple selections

When multi-editing (Ctrl+select) is enabled, and there are 2 selections, then Ctrl+T (Transpose) should swap the contents of those 2 selections. This should not affect the clipboard, and it should not affect which selection-position is the main selection. If there is only 1 selection, Ctrl+T should do as it does now (transpose lines). If there are 3 or more selections it should rotate their contents.

The same should apply to the rows of a rectangular or column selection (Alt-select) irrespective of whether multi-editing is enabled.

The Edit menu should contain an item "Transpose Ctrl+T". It might change from "Transpose Lines" to "Transpose Selections" to "Transpose Rows" depending on the nature of the selection(s).

This feature exists in Sublime Text:
https://stackoverflow.com/questions/16801313/swapping-text-selections-in-sublime-text-2
and in Visual Studio (via a plug-in):
https://marketplace.visualstudio.com/items?itemName=SSDiver2112.SwapSelection