Drag to Select Export Composite

When we choose the export composite, add the ability to choose a part of the map to export as composite instead of the entire map. Simply drag a rectangle over the area that you want to export, and only that area gets exported.

This helps having similar composites in a single map, we can edit all items of a set at the same time. For example if we have made 10 emblems, these could be selected to be exported.