Warn when overwriting saved layout

[vertigo]

As the title says. If you save a layout, then make changes and save the current layout with those changes as the same layout you previously saved, it will overwrite your previously setup layout without warning.

[tboy]

+1

[m.Th.]

+1

...also the possibility to enter a name for the layout would be very nice.

[m.Th.]

In fact if we have names, then no check is necessary: a name means that something is already in there.

[vertigo]

Still necessary, in case you accidentally select the wrong one. But yes, names could be useful.