copy closedbox description to basedbox description as applicable

boxes/generators/closedbox.py

@@ -22,6 +22,10 @@ class ClosedBox(Boxes):
 
     ui_group = "Box"
 
+    description = """This box is more of a building block than a finished item.
+Use a vector graphics program (like Inkscape) to add holes or adjust the base
+plate."""
+
     def __init__(self):
         Boxes.__init__(self)
         self.addSettingsArgs(edges.FingerJointSettings)