Implement "Specify On-screen (Once)" for drawing recess in element

A while ago we presented a new feature for Recesses which gave you the option to select visually what side you wanted to add your recess to.

That feature was called 'Specify on-screen'.

We have now expanded that feature, the old selection is now called 'Specify on-screen (for each)' and then we have added 'Specify on-screen (once)'

This means that if you select 'Specify on-screen (once)' you select the plane that you want to be working with and you can add as many recesses to that plane until you exit the function.

The 'Specify on-screen (for each)' is the same as the old function, that is, you can add the same recess on any surface of the element and not be restricted to one plane.