fix: rght borders maximized/fullscreen windows

fixes #6

awesome/src/core/signals.lua

@@ -24,9 +24,13 @@ client.connect_signal(
             awful.placement.no_offscreen(c)
         end
         c.shape = function(cr, width, height)
+            if c.fullscreen or c.maximized then
+                gears.shape.rectangle(cr, width, height)
+            else
                 gears.shape.rounded_rect(cr, width, height, 10)
             end
         end
+    end
 )
 
 client.connect_signal(